Do we need to log OTLP errors at SEVERE and FINEST?

[jack-berg]

Copy / pasted from GrpcExporter, which has a similar, but not identical, harness / wrapper around GrpcSender.

Tracked the lineage of where this additional finest level logging came from and its ancient: https://github.com/open-telemetry/opentelemetry-java/pull/1803/changes#diff-b81bcc3e91a1ea9ee5f99b101f968b51a9396151014479db2f00e419394b573fR149

But it does seem duplicative. At the SEVERE level, the exception is included, and thus can be printed if the user has configured their logging framework to do so. At the FINEST level, the stacktrace is printed as part of the log message regardless of logging framework config.

Originally posted by @jack-berg in #8046 (comment)

[ps-mir]

I think FINEST can be ditched unless its logging something useful for internal debugging and non-overlapping with SEVERE