feat(catalog): Implement MemoryCatalog's table update/ commit path

[DerGut]

This is a copy of #1290. Reopened here for reference.

Which issue does this PR close?

Relates to #700

This is a first attempt at implementing the commit path for the MemoryCatalog. Happy about any feedback!

What changes are included in this PR?

This PR implements the MemoryCatalog::update_table method. It also adds a MetadataLocation struct to avoid some re-validations of the location format.
I'm very open to removing the MetadataLocation or moving it's addition to a separate PR.

Are these changes tested?

So far, I've included unit tests to verify

• whether a table update that was committed via the MemoryCatalog can be observed in the updated table
• that in the case of two competing updates, the later commit fails if it has conflicting requirements
• that an update fails if the table isn't known to the catalog
• parsing logic of the MetadataLocation