Reduce verbosity when checking if package embeds ECS

[jsoriano]

We are logging now Package does not embed ECS mappings every time we check if we should embed ECS mappings because they are referenced in the package.
This is not so relevant because the final reason to import ECS schema during validation depends on two other variables at the moment, but it sometimes floods the logs. For example when running the pipeline tests of the Azure package, this line is printed 33 times in a row, and is not deterministic on its own for the actual result.

This change removes this debug log, and when the mappings are effectively considered for fields validation, the possible reasons for importing are printed too.

[elasticmachine]

💛 Build succeeded, but was flaky

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• Commit: 5e99b36

Failed CI Steps

• :go: Integration test: benchmarks

History

• 💚 Build #2824 succeeded 9fef93a

cc @jsoriano