Use catch :default for default error handling in cljs

This is considered normal practice for cljs. See
https://clojure.atlassian.net/browse/CLJS-661 for when it was introduced
and background on it

src/main/frontend/handler/block.cljs

@@ -234,7 +234,7 @@
 
             :else
             nil))
-        (catch js/Error e
+        (catch :default e
           (js/console.error e))
         (finally
           (reset! *show-left-menu? false)