Reduce coverage log spam

[kirschem-fernride]

Given a large enough scope, the coverageoutputgenerator produces lots of log lines that are not really meaningful.

Apr 19, 2024 4:14:03 PM com.google.devtools.coverageoutputgenerator.Main parseFilesSequentially
INFO: Parsing file bazel-out/k8-fastbuild/testlogs/X/Y/Z/coverage.dat
Apr 19, 2024 4:14:03 PM com.google.devtools.coverageoutputgenerator.Main parseFilesSequentially
INFO: Parsing file bazel-out/k8-fastbuild/testlogs/A/B/C/coverage.dat

This PR changes the log level to make it less verbose by default.

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[fmeum]

@kirschem-fernride I just sent #22257.

[kirschem-fernride]

@fmeum Awesome, thx! I will close this PR then. Do you know at what cadence the remote_coverage_tools are updated?

[fmeum]

I think it's updated whenever there has been a meaningful change to it and a Bazel release is coming up, but that doesn't happen too often.