Add WARN message when OtlpMeterRegistry fails to publish metrics

[antechrestos]

Experienced this bad behaviour while plugging my application to an APM; as I configured the bad endpoint, it answered me with 403 http status, yet nothing appeared in logs, as if everything was normal. I had to use debugger to see the status.

[pivotal-cla]

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[jonatan-ivanov]

Thank you for the PR!
I think this makes sense. I believe we should do this on the 1.10.x branch so not only 1.12 but 1.11 and 1.10 will get this fix. Could you please rebase your changes on the 1.10.x branch?

[antechrestos]

@jonatan-ivanov of course. I will do it by tomorrow with your suggestion.
Thank you

[antechrestos]

@jonatan-ivanov I made the following change

• applied suggestion
• change target branch (with rebase)

Cheers

[jonatan-ivanov]

Thank you!

[antechrestos]

@jonatan-ivanov do i need to report the change on other branches? Which ones? I spotted that code was not really the same...

[jonatan-ivanov]

Nope, once it is merged to a maintenance branch the person who merged it should forward merge it to the other supported branches too. I've already taken care of forward merging and resolving the merge conflicts (as you noticed, the code changed a bit). This change is now available on 1.10.x, 1.11.x, and main, see 538ba6a and 32fe2c5

You can try out any latest snapshot versions, e.g.: 1.12.0-SNAPSHOT, it should contain your changes, thank you again for fixing this!