[HttpClient and ASP.NET Core] Fix failures due to changes in .NET8.0 stable release

[vishweshbankwar]

Fixes #
Design discussion issue #

Changes

Fixes couple of failures due to upgrade to .NET8.0. These are expected changes based on the issues that were fixed between rc and table release.

Merge requirement checklist

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

[codecov]

Codecov Report

Merging #5049 (ccc04e9) into main (ecb5dc8) will decrease coverage by 0.02%.
The diff coverage is n/a.

❗ Current head ccc04e9 differs from pull request most recent head 4a41a41. Consider uploading reports for the commit 4a41a41 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5049      +/-   ##
==========================================
- Coverage   83.35%   83.34%   -0.02%     
==========================================
  Files         296      296              
  Lines       12474    12473       -1     
==========================================
- Hits        10398    10395       -3     
- Misses       2076     2078       +2     

Flag	Coverage Δ
unittests	83.34% <ø> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...AspNetCore/Implementation/HttpInMetricsListener.cs	89.39% <ø> (-0.16%)	⬇️

... and 5 files with indirect coverage changes

[cijothomas]

interesting...there is no code change here. Do we plan to keep updating changelog in otel instrumentation, for every change in .net repo? Or this is a one-time thing and we dont expect anything futher?

[vishweshbankwar]

I mentioned this one because we have a changelog entry in previous release with different name. In future, I don't think we need to mention every change. Except when the change might impact users moving from lower version to net8 or above.

[utpilla]

Going forward, I think we should simply update the README to point to the Microsoft official docs which lists these metrics and let users track the changes from there.