fix(baggage): include baggage metadata when propagating baggage entries

[chrskrchr]

Which problem is this PR solving?

Partially fixes #2740

Short description of the changes

As part of the changes to address #2740, the W3CBaggagePropagator needs to be updated to propagate baggage entry metadata. It was previously parsing the metadata on baggage extraction from the inbound request but not including it on propagation.

Type of change

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

This PR might also be considered a "bug fix" since it's adding functionality that was expected to already be in place.

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• added unit test assertion
• verified in local application that baggage metadata is now being propagated

Checklist:

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

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Chris Karcher (b473d1e)

[vmarchaud]

@chrskrchr You'll need to sign the CLA so we can accept the PR

[codecov]

Codecov Report

Merging #2766 (aff56e2) into main (4f8849f) will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2766      +/-   ##
==========================================
- Coverage   93.29%   93.28%   -0.02%     
==========================================
  Files         159      159              
  Lines        5445     5448       +3     
  Branches     1143     1144       +1     
==========================================
+ Hits         5080     5082       +2     
- Misses        365      366       +1     

Impacted Files	Coverage Δ
packages/opentelemetry-core/src/baggage/utils.ts	75.75% <100.00%> (+2.42%)	⬆️
...emetry-core/src/platform/node/RandomIdGenerator.ts	87.50% <0.00%> (-6.25%)	⬇️

[chrskrchr]

@chrskrchr You'll need to sign the CLA so we can accept the PR

Yep! Working on that with my organization now since I'm technically a "corporate contributor". I'll move this PR out of draft mode as soon as I have that sorted.

[chrskrchr]

@vmarchaud - my CLA has been approved and this PR is ready for review.

I see you added the bug tag to the PR. Would you prefer I include the fix prefer on the PR title so it's released as a patch/fix change?

[vmarchaud]

Would you prefer I include the fix prefer on the PR title so it's released as a patch/fix change?

I believe its based on the PR tag, but yeah i think its preferable since we should have propagated since in the first place

[legendecas]

Thank you for the work!