tag: Fix removing tags for maintenance templates where |name= points to a redirect

[9382]

For #1863/#1618

If a maintenance template had been moved but its |name= wasn't updated, the code would pick up every version of that template except for the current name (since obviously that won't appear in a linkshere for itself and it tries to use the |name= for its current name). This fixes that by ensuring that whatever page linkshere resolves to is also included in the templates it attempts to remove

Credit to #1618 for the solution, I just tested it to make sure it worked

(Testing) Fixes #1618

[NovemLinguae]

I can't get #1618 to link. Note to self: when merging this, manually close #1618.

[9382]

Managed to get it to link by editing my original comment to include some keywords