delete or un-multitenant `TestTransientClusterMultitenant`

[iliana]

cockroach/pkg/cli/democluster/demo_cluster_test.go

Lines 257 to 258 in afda0c1

	func TestTransientClusterMultitenant(t *testing.T) {
	skip.IgnoreLint(t, "tenant connector requires a CCL binary")

Not immediately clear to me if this test is testing something we otherwise wouldn't be if we deleted it.