Add config file for the markdown checker

[breedx-splk]

This moves the configuration for the linkdown checker from commandline args over to a toml config file. This is intended to improve consistency between the java repos, and aligns with contrib #1986 and others.

Might need a refresh after open-telemetry/opentelemetry-java-instrumentation#14155 goes in.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.12%. Comparing base (1e763b2) to head (5800219).
⚠️ Report is 81 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #7460   +/-   ##
=========================================
  Coverage     90.12%   90.12%           
  Complexity     7187     7187           
=========================================
  Files           814      814           
  Lines         21700    21700           
  Branches       2123     2123           
=========================================
  Hits          19557    19557           
  Misses         1477     1477           
  Partials        666      666           

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[breedx-splk]

I want this to align with open-telemetry/opentelemetry-android#1037 and open-telemetry/opentelemetry-java-contrib#1986 and open-telemetry/opentelemetry-java-instrumentation#14155 so making draft...

[jkwatson]

Thanks!

[zeitlinger]

This is the new template that @trask has created: https://github.com/open-telemetry/opentelemetry-java-contrib/blob/main/.github/workflows/reusable-link-check.yml

[jkwatson]

@breedx-splk is this ready to go?

[breedx-splk]

No, I think I should probably just close it and make a new one that realigns better with the template that changed before I could come back to it. Sorry.