Registry: add support for versioned ensembl_metadata DBs [release/96]

Created by: mkszuba

Description

Extend the Registry so that it can detect Ensembl metadata databases whose names contain the release number, with backward compatibility with unversioned databases but preference for versioned ones if both forms are present.

Backport of #379 to release/96.

Use case

Since release 96 Ensembl metadata databases have been named ensembl_metadata_XY, where XY is the release number. Unfortunately the Registry has not been updated accordingly so it keeps looking for ensembl_metadata. See ENSCORESW-3119 for additional information.

Benefits

Registry will be able to correctly instantiate MetadataDBAdaptors again.

Possible Drawbacks

A slight increase in computational overhead during Registry initialisation, primarily due to the fact we retain backward compatibility with the old naming convention.

Testing

Have you added/modified unit tests to test the changes?

No.

If so, do the tests pass/fail?

N/A

Have you run the entire test suite and no regression was detected?

Yes, no regression detected (tests fail but in the same way both before and after the commit at hand).