31sync/09archived: "Newly left rooms appear in the leave section of gapped sync": possible bug in not creating the filter properly

[ShadowJonathan]

sytest/tests/31sync/09archived.pl

Lines 185 to 189 in 3871417

	my $filter = {
	room => { timeline => { limit => 1 }, include_leave => JSON::true }
	};
	matrix_create_filter( $user, {} )->then( sub {

My IDE highlighted the $filter here as "not used";

It is possible that this might have caused this test to not run correctly for 7 years (since 2015)