Bugfix jaeger exporter test panic

[hanyuancheung]

This PR adds logic to determine if the channel is closed to fix jaeger exporter test panic with close of closed channel.

Resolves #1870

[hanyuancheung]

Hi, I'm a first-time contributor, could anybody help to approve running these workflows, great thx~

[hanyuancheung]

When running the ci / test-coverage, something wrong happened with:
{'detail': ErrorDetail(string='Unable to locate build via Github Actions API. Please upload with the Codecov repository upload token to resolve issue.', code='not_found')}
How to solve this problem, could we just rerun the workflow or anything else?

[codecov]

Codecov Report

Merging #1973 (c11a4eb) into main (4949bf0) will increase coverage by 0.6%.
The diff coverage is 89.7%.

@@           Coverage Diff           @@
##            main   #1973     +/-   ##
=======================================
+ Coverage   76.5%   77.1%   +0.6%     
=======================================
  Files        160     161      +1     
  Lines       8495    8554     +59     
=======================================
+ Hits        6503    6602     +99     
+ Misses      1733    1696     -37     
+ Partials     259     256      -3     

Impacted Files	Coverage Δ
bridge/opentracing/internal/mock.go	69.3% <31.5%> (-3.4%)	⬇️
bridge/opentracing/bridge.go	46.4% <45.4%> (-1.5%)	⬇️
baggage/baggage.go	98.9% <98.9%> (-1.1%)	⬇️
baggage/context.go	100.0% <100.0%> (ø)
internal/baggage/context.go	100.0% <100.0%> (ø)
propagation/baggage.go	100.0% <100.0%> (+13.6%)	⬆️
sdk/trace/batch_span_processor.go	87.1% <0.0%> (+1.5%)	⬆️

[MrAlias]

When running the ci / test-coverage, something wrong happened with:
{'detail': ErrorDetail(string='Unable to locate build via Github Actions API. Please upload with the Codecov repository upload token to resolve issue.', code='not_found')}
How to solve this problem, could we just rerun the workflow or anything else?

It seems like the codecov endpoint is having issues today. I have seen quite a lot of this error in other PRs. Rerunning can resolve the issue as it looks like it is an instability on the receiving side, not our sending side.