Fix ImportError for configure_logging

[stefsmeets]

Description

We recently moved the logging configuration to its own submodule in esmvalcore. This PR fixes a potential ImportError in esmvaltool.

• Addresses: Importing private functions and variables from esmvalcore #1975

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[valeriupredoi]

OK good catch, just gonna wait for numpy to come back then rerun the tests 👍

[valeriupredoi]

tests are dying because of this #1980 - nothing to do with your PR, mate 👍

[valeriupredoi]

go for it, cheers for the fix!

[bouweandela]

This should only have been merged after the release of ESMValCore v2.2. Please do not merge pull requests with failing tests. If you had looked carefully through the test failures, you would have seen that this pull request introduces additional failing unit tests.

[valeriupredoi]

This should only have been merged after the release of ESMValCore v2.2. Please do not merge pull requests with failing tests. If you had looked carefully through the test failures, you would have seen that this pull request introduces additional failing unit tests.

@bouweandela see me comment on the reversal PR, mate 👍

[bouweandela]

Sorry this was merged too early @stefsmeets, we had to revert it for now. Could you please make a new pull request with these changes?

[stefsmeets]

#1994

[bouweandela]

Thanks!