Improvement: Log the thrown error while validating extracted package cache

[johnhany97]

Before this PR

When an error is thrown when validating the extracted package cache, the following is seen:

debug    libmamba Verify cache '/home/circleci/micromamba/pkgs' for package extracted directory '_libgcc_mutex-0.1-main'
warning  libmamba Extracted package cache '/home/circleci/micromamba/pkgs/_libgcc_mutex-0.1-main' is invalid'
debug    libmamba '_libgcc_mutex-0.1-main' extracted directory cache is invalid
error    libmamba Cannot find a valid extracted directory cache for '_libgcc_mutex-0.1-main.tar.bz2'

After this PR

The actual error encountered is no longer swallowed and is instead logged to help the user debug the issue further.

[wolfv]

thanks!