BUGFIX: Don't flush if tags is an empty array

FOS Varnish will call array_chunk on the given tags with
the size of the tags array. If the tags are empty, an error
is thrown.

Classes/Aspects/ContentCacheAspect.php

@@ -129,8 +129,10 @@ public function registerDisableContentCache(JoinPointInterface $joinPoint): void
     public function interceptContentCacheFlush(JoinPointInterface $joinPoint)
     {
         $object = $joinPoint->getProxy();
-
         $tags = array_keys(ObjectAccess::getProperty($object, 'tagsToFlush', true));
+        if ($tags === []) {
+          return;
+        }
 
         $this->varnishBanService->banByTags($tags);
     }