Guy Sartorelli 19bb72e7c7 FIX Correctly remove relations with ManyManyThroughList::removeall
Instead of just setting one side of the relation to null in the through
list, remove the rows entirely.
Remove only the relations which match the filters that have already been
set on the list.
This is consistent with the way ManyManyList works.

Also some small tidy-up (removing an unnecessary line break and an
unused "use" statement)
2022-05-05 11:21:51 +12:00
..