Update supported Cinnamon versions

Author: anaximeno

mouse-click-effects@anaximeno/files/mouse-click-effects@anaximeno/metadata.json

@@ -11,6 +11,7 @@
         "5.8",
         "6.0",
         "6.2",
-        "6.4"
+        "6.4",
+        "6.6"
     ]
 }