⚡ simpler API check as according to plotly/dash@7281b7d

Author: chriddyp

Diff for: src/actions/index.js

@@ -500,11 +500,7 @@ function updateOutput(
     }
 
     // Clientside hook
-    if (
-        clientside_function &&
-        // allow the API to skip clientside if provided {} or nothing at all
-        !isEmpty(clientside_function)
-    ) {
+    if (clientside_function) {
         let returnValue;
         try {
             returnValue = window.dash_clientside[clientside_function.namespace][