Fixed: Ignore empty tags when adding items to Flood

Fixed #8145

src/NzbDrone.Core/Download/Clients/Flood/Flood.cs

@@ -78,7 +78,7 @@ private static IEnumerable<string> HandleTags(RemoteMovie remoteMovie, FloodSett
                 }
             }
 
-            return result;
+            return result.Where(t => t.IsNotNullOrWhiteSpace());
         }
 
         public override string Name => "Flood";