feat(opentelemetry-config): set headers from headers_list

[JamieDanielson]

Which problem is this PR solving?

Set headers from headers_list if headers doesn't exist

Short description of the changes

Set headers from headers_list if headers doesn't exist

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• unit test

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added

[codecov]

Codecov Report

❌ Patch coverage is 66.66667% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.10%. Comparing base (e460f03) to head (38bda18).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
...ntelemetry-configuration/src/FileConfigProvider.ts	66.66%	8 Missing ⚠️

❌ Your patch check has failed because the patch coverage (66.66%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6060      +/-   ##
==========================================
- Coverage   95.16%   95.10%   -0.07%     
==========================================
  Files         316      316              
  Lines        9207     9231      +24     
  Branches     2075     2079       +4     
==========================================
+ Hits         8762     8779      +17     
- Misses        445      452       +7     

Files with missing lines	Coverage Δ
...ntelemetry-configuration/src/FileConfigProvider.ts	93.15% <66.66%> (-0.89%)	⬇️

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[maryliag]

code looks good, you will just need more tests. It's hard to get tests for all possible options, it takes some work 😓

[JamieDanielson]

I'm holding off on adding the last bit of tests because there are some pretty major merge conflicts with the other changes 😅 If these don't get added into the other PRs, I'll update this after the others merge.

[maryliag]

oops, I'mm not making your life easier with all my changes 😅