tar: remove strconv dependency for tar checksum octal numbers

[gabriel-vasile]

goos: linux
goarch: amd64
pkg: github.com/gabriel-vasile/mimetype
cpu: Intel(R) Core(TM) i7-10510U CPU @ 1.80GHz
               │ common_master │              common_dev              │
               │    sec/op     │    sec/op     vs base                │
Common/.xlsx-8    401.2n ±  3%   312.2n ±  5%  -22.17% (p=0.000 n=10)
Common/.pptx-8    1.708µ ±  4%   1.535µ ±  3%  -10.10% (p=0.000 n=10)
Common/.docx-8    1.260µ ±  7%   1.116µ ±  4%  -11.43% (p=0.000 n=10)
Common/.tar-8    1011.0n ±  7%   785.0n ±  4%  -22.35% (p=0.000 n=10)
Common/.zip-8     742.3n ± 11%   616.2n ± 16%  -16.99% (p=0.003 n=10)
Common/.pdf-8     291.6n ±  4%   191.9n ±  4%  -34.20% (p=0.000 n=10)
Common/.jpg-8     410.7n ±  9%   374.1n ± 17%   -8.90% (p=0.019 n=10)
Common/.png-8     425.1n ±  8%   327.8n ±  8%  -22.89% (p=0.000 n=10)
Common/.gif-8     480.4n ±  4%   396.9n ±  7%  -17.38% (p=0.000 n=10)
Common/.xls-8     427.2n ±  6%   324.7n ±  4%  -24.00% (p=0.000 n=10)
Common/.webm-8   1160.0n ±  5%   724.8n ±  5%  -37.52% (p=0.000 n=10)
Common/.csv-8     6.965µ ±  7%   5.671µ ±  6%  -18.57% (p=0.000 n=10)
geomean           784.9n         620.0n        -21.01%

               │ common_master │              common_dev               │
               │     B/op      │     B/op      vs base                 │
Common/.xlsx-8      312.0 ± 0%     312.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.pptx-8      592.0 ± 0%     592.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.docx-8      504.0 ± 0%     504.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.tar-8       200.0 ± 0%     192.0 ± 0%  -4.00% (p=0.000 n=10)
Common/.zip-8       224.0 ± 0%     224.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.pdf-8       192.0 ± 0%     192.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.jpg-8       192.0 ± 0%     192.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.png-8       192.0 ± 0%     192.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.gif-8       192.0 ± 0%     192.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.xls-8       288.0 ± 0%     288.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.webm-8      192.0 ± 0%     192.0 ± 0%       ~ (p=1.000 n=10) ¹
Common/.csv-8     7.390Ki ± 0%   7.323Ki ± 0%  -0.90% (p=0.000 n=10)
geomean             339.8          338.4       -0.41%
¹ all samples are equal

               │ common_master │              common_dev              │
               │   allocs/op   │ allocs/op   vs base                  │
Common/.xlsx-8      4.000 ± 0%   4.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.pptx-8      15.00 ± 0%   15.00 ± 0%        ~ (p=1.000 n=10) ¹
Common/.docx-8      13.00 ± 0%   13.00 ± 0%        ~ (p=1.000 n=10) ¹
Common/.tar-8       3.000 ± 0%   2.000 ± 0%  -33.33% (p=0.000 n=10)
Common/.zip-8       6.000 ± 0%   6.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.pdf-8       2.000 ± 0%   2.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.jpg-8       2.000 ± 0%   2.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.png-8       2.000 ± 0%   2.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.gif-8       2.000 ± 0%   2.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.xls-8       3.000 ± 0%   3.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.webm-8      2.000 ± 0%   2.000 ± 0%        ~ (p=1.000 n=10) ¹
Common/.csv-8       34.00 ± 0%   31.00 ± 0%   -8.82% (p=0.000 n=10)
geomean             4.349        4.173        -4.06%
¹ all samples are equal

            │ rand_master │              rand_dev               │
            │   sec/op    │   sec/op     vs base                │
SliceRand-8   457.4n ± 4%   398.1n ± 3%  -12.96% (p=0.000 n=10)

            │ rand_master │              rand_dev              │
            │    B/op     │    B/op     vs base                │
SliceRand-8   160.00 ± 0%   96.00 ± 0%  -40.00% (p=0.000 n=10)

            │ rand_master │              rand_dev              │
            │  allocs/op  │ allocs/op   vs base                │
SliceRand-8    4.000 ± 0%   1.000 ± 0%  -75.00% (p=0.000 n=10)