All the setup/teardown/pre/post/conditions template methods
now are required to return void. This was warned with phpunit 7
and now is enforced.
At the same time, fix a few wrong function names,
provider data and param types, return statements...
In a Single Simple Discussion forum, the first post can only be edited
by a user with the manageactivities capability, but all other posts
behave as normal.
Eloy Lafuente (stronk7)