🚨 Test: improve benchmarks for getOffer

[nickajacks1]

Description

Split getOffers benchmarks into individual cases for easier analysis.
This makes explicit two scenarios with allocations:

1. The Accept contains 3 or more media type parameters: the code uses a stack allocated slice of length 2, so this is expected.
2. The Accept contains an unknown mime extension (in this case iso-8859-1). I'm not sure if this is expected or not.

Benchmarks

Benchmark_Utils_GetOffer/simple-8               37348665                31.14 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/simple-8               37296252                31.19 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/simple-8               37496180                31.25 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/simple-8               37886322                31.41 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers-8             14654864                80.64 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers-8             14888724                80.79 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers-8             15045030                85.98 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers-8             14630626                80.58 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/1_parameter-8          12318861                98.65 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/1_parameter-8          12215715                99.23 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/1_parameter-8          11927502               102.7 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/1_parameter-8          12524857                98.15 ns/op            0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/2_parameters-8          7165609               161.8 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/2_parameters-8          7047482               162.1 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/2_parameters-8          7245342               161.5 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/2_parameters-8          7477488               162.5 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/3_parameters-8          3653287               329.7 ns/op           128 B/op          1 allocs/op
Benchmark_Utils_GetOffer/3_parameters-8          3639289               328.2 ns/op           128 B/op          1 allocs/op
Benchmark_Utils_GetOffer/3_parameters-8          3661699               326.4 ns/op           128 B/op          1 allocs/op
Benchmark_Utils_GetOffer/3_parameters-8          3660715               328.0 ns/op           128 B/op          1 allocs/op
Benchmark_Utils_GetOffer/10_parameters-8          972722              1158 ns/op             896 B/op          3 allocs/op
Benchmark_Utils_GetOffer/10_parameters-8          982041              1157 ns/op             896 B/op          3 allocs/op
Benchmark_Utils_GetOffer/10_parameters-8          948860              1153 ns/op             896 B/op          3 allocs/op
Benchmark_Utils_GetOffer/10_parameters-8         1000000              1151 ns/op             896 B/op          3 allocs/op
Benchmark_Utils_GetOffer/6_offers_w/params-8             4526132               267.6 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers_w/params-8             4521868               262.9 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers_w/params-8             4501616               282.0 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/6_offers_w/params-8             4294874               267.2 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension-8                6349107               201.9 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension-8                6271616               188.5 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension-8                6190488               193.3 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension-8                6397099               205.7 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension#01-8             4531942               265.0 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#01-8             4464699               264.2 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#01-8             4533716               263.1 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#01-8             4529667               265.0 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#02-8             2966164               405.5 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#02-8             2920989               406.7 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#02-8             2968666               403.8 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#02-8             2940620               405.1 ns/op            48 B/op          2 allocs/op
Benchmark_Utils_GetOffer/mime_extension#03-8             6550610               184.1 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension#03-8             6341877               197.2 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension#03-8             6697556               188.6 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/mime_extension#03-8             6748568               192.4 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/web_browser-8                  10075825               124.1 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/web_browser-8                  10330788               111.5 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/web_browser-8                  10692439               117.3 ns/op             0 B/op          0 allocs/op
Benchmark_Utils_GetOffer/web_browser-8                   9933765               124.0 ns/op             0 B/op          0 allocs/op

Type of change

Please delete options that are not relevant.

• Unit Tests

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I tried to make my code as fast as possible with as few allocations as possible
• For new code I have written benchmarks so that they can be analyzed and improved