Fix failing failing testWatcherRestart (#35243)

Reenabling the test on 6.x as  #35271 looks like fixed the problem. If that helps on 6.x it will be back ported to 6.6, 6.5 and previous versions where this test is muted.

closes #33753

Author: pgomulka

x-pack/qa/rolling-upgrade/src/test/java/org/elasticsearch/upgrades/WatchBackwardsCompatibilityIT.java

@@ -177,9 +177,9 @@ public void testWatcherStats() throws Exception {
         );
     }
 
-    @AwaitsFix(bugUrl="https://github.com/elastic/elasticsearch/issues/33753")
     public void testWatcherRestart() throws Exception {
         executeUpgradeIfNeeded();
+        ensureWatcherStarted();
 
         executeAgainstRandomNode(client -> assertOK(client.performRequest("POST", "/_xpack/watcher/_stop")));
         ensureWatcherStopped();