[release] Core stable release 1.20.0 updates

[otelbot-dotnet]

Note: This PR was opened automatically by the post-release workflow.

Merge once packages are available on NuGet and the build passes.

Changes

• Sets OTelLatestStableVer in Directory.Packages.props to 1.20.0.

[opentelemetry-pr-dashboard]

Pull request dashboard status

Merged · refreshed 2026-10-15 14:55 UTC

Status above doesn't look right?

• Anything look wrong? Report it with what you expected; it helps us improve the dashboard.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.29%. Comparing base (d5b2f8a) to head (4d226d4).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7950      +/-   ##
==========================================
- Coverage   92.36%   92.29%   -0.07%     
==========================================
  Files         363      363              
  Lines       21035    21035              
==========================================
- Hits        19428    19415      -13     
- Misses       1607     1620      +13     

Flag	Coverage Δ
unittests-PowerShellScripts	87.43% <ø> (ø)
unittests-Project-Experimental	92.42% <ø> (ø)
unittests-Project-Stable	92.42% <ø> (-0.06%)	⬇️
unittests-Solution	92.41% <ø> (+0.05%)	⬆️
unittests-UnstableCoreLibraries-Experimental	45.25% <ø> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.
see 4 files with indirect coverage changes