catalog: add api to fetch service's port:protocol mapping across prov…

[shashankram]

Description:
Adds an api to the MeshCataloger interface to fetch the port:protocol
mapping for a service's ports. Some safety checks have been put in place
to ensure the port:protocol mapping for a service's endpoints is the
same across providers.

Affected area:

• New Functionality [ ]
• Documentation [ ]
• Install [ ]
• Control Plane [X]
• CLI Tool [ ]
• Certificate Management [ ]
• Networking [ ]
• Metrics [ ]
• SMI Policy [ ]
• Security [ ]
• Tests [ ]
• CI System [ ]
• Performance [ ]
• Other [ ]

Please answer the following questions with yes/no.

• Does this change contain code from or inspired by another project? If so, did you notify the maintainers and provide attribution?
  No

[codecov-io]

Codecov Report

Merging #2137 (f010b97) into main (27379ac) will decrease coverage by 0.43%.
The diff coverage is 16.12%.

@@            Coverage Diff             @@
##             main    #2137      +/-   ##
==========================================
- Coverage   58.28%   57.84%   -0.44%     
==========================================
  Files         143      144       +1     
  Lines        5933     5995      +62     
==========================================
+ Hits         3458     3468      +10     
- Misses       2472     2524      +52     
  Partials        3        3              

Impacted Files	Coverage Δ
pkg/catalog/mock_catalog.go	0.00% <0.00%> (ø)
pkg/endpoint/mock_provider.go	0.00% <0.00%> (ø)
pkg/catalog/service.go	91.66% <83.33%> (-8.34%)	⬇️

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