MM-25040: Restrict associated groups to channels when team is group-constrained. (#14619)

* MM-25040: Only return team-associated groups if the team is group-constrained.
MM-25040: Prevents associating a group to a channel if the team doesn't have the group first.

* MM-25040: Fix lints.

* MM-25040: Still add the groupteam if the team is not group-constrained.

* MM-25040: Wraps groupteam upsert in else branch for efficiency.

* MM-25040: Removes unnecessary page iteration.

* MM-25040: Fix typo.

* MM-25040: Moves filtering to SQL.

* MM-25040: Updates tests, check pagination.

* MM-25040: Fix lint error.

* MM-25040: Adds some more group store tests.

* MM-25040: Fix for wrong test parameter.

model/group.go

@@ -81,6 +81,12 @@ type GroupSearchOpts struct {
 	FilterAllowReference   bool
 	PageOpts               *PageOpts
 	Since                  int64
+
+	// FilterParentTeamPermitted filters the groups to the intersect of the
+	// set associated to the parent team and those returned by the query.
+	// If the parent team is not group-constrained or if NotAssociatedToChannel
+	// is not set then this option is ignored.
+	FilterParentTeamPermitted bool
 }
 
 type PageOpts struct {