URL Alias of Taxonomy term is not exported

Uploaded a variant of my patch 16, re-rolled to include upstream changes, and that uses $this->entityTypeManager(). I didn't try to use dependency injection, as it seems that would require bigger changes.

Ugh, redone, undoing the changes to use $this->entityTypeManager(). One can hardly use that in `static` methods.

mparker17 → changed the visibility of the branch 3074288-url-alias-of to hidden.

To make this easier to review, I've rebased the merge request onto the latest 2.x.

A brief glance at the code in the merge request suggests that it has no tests. The Structure Sync maintainers prefer to accept merge requests that have passing automated tests. If you need help writing tests, please ask: I would be happy to help!