Increase TestHangingNotifier timeout

This test keeps timing out on our arm64 CI server, it does use a very slow timeout and that 5ms doesn't seem to be enough.
But it 10x.

Signed-off-by: Lukasz Mierzwa <lukasz@cloudflare.com>

notifier/notifier_test.go

@@ -711,7 +711,7 @@ func TestHangingNotifier(t *testing.T) {
 	)
 
 	var (
-		sendTimeout = 10 * time.Millisecond
+		sendTimeout = 100 * time.Millisecond
 		sdUpdatert  = sendTimeout / 2
 
 		done = make(chan struct{})