chore: Prepare for opentelemetry-appender-tracing 0.30.1 - bump tracing-opentelemetry to 0.31

[lalitb]

Fixes #
Design discussion issue (if applicable) #

Changes

Please provide a brief description of the changes here.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

Attention: Patch coverage is 98.19820% with 2 lines in your changes missing coverage. Please review.

Project coverage is 81.1%. Comparing base (51dc2f0) to head (faf259d).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
opentelemetry-appender-tracing/src/layer.rs	98.1%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #3022     +/-   ##
=======================================
+ Coverage   81.0%   81.1%   +0.1%     
=======================================
  Files        126     126             
  Lines      24868   24954     +86     
=======================================
+ Hits       20152   20255    +103     
+ Misses      4716    4699     -17     

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[lalitb]

Something wrong in the CI, not related to the PR changes:

The job was not acquired by Runner of type hosted even after multiple attempts
--
Internal server error. Correlation ID: 509b5dab-08ee-4552-9c89-6efad897b563

[lalitb]

published to crates.io