[internal/tools] Add support for modernize in Makefile

[paulojmdias]

Description

Added a new modernize make target to run the Go modernize tool. This isn’t part of CI, users need to run it manually when they want to apply modern Go patterns.

Same as open-telemetry/opentelemetry-collector-contrib#42542

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.38%. Comparing base (62c505f) to head (25df519).
⚠️ Report is 12 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13800      +/-   ##
==========================================
- Coverage   91.43%   91.38%   -0.05%     
==========================================
  Files         641      641              
  Lines       42670    42670              
==========================================
- Hits        39016    38996      -20     
- Misses       2835     2850      +15     
- Partials      819      824       +5     

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[paulojmdias]

@songy23 @jmacd I rebased the branch and ran make gotidy to fix the conflicts 🙏

[codeboten]

this looks ok to me, do you have an example of what changes modernize proposes? i haven't used it before

[paulojmdias]

@codeboten one PR example open-telemetry/opentelemetry-collector-contrib#42596

But you can find all the details here

I'm not sure if this should be added to the CI, but maybe it should be something to evaluate in the future.

[codeboten]

Thanks @paulojmdias