This reverts commit 62e1fb0b5f.
Reason for revert: caused several errors:
* unnamespaced HooksTest collides with core’s class of the same name
* Scribunto_LuaError renamed without class alias despite being used in Wikibase
Bug: T314464
Change-Id: I8b151327236bf86945e59823fba155497e4b3fc6
And use the unit test base on most of the tests, except the ones that need
database. This makes tests considerably faster.
Bug: T230701
Change-Id: Ifbede1e2610c672b4d8a83ce41f74200e0c97be9