feat: Add JavaScript action template

https://github.com/actions/javascript-action

wait.js

@@ -0,0 +1,11 @@
+let wait = function(milliseconds) {
+  return new Promise((resolve, reject) => {
+    if (typeof(milliseconds) !== 'number') { 
+      throw new Error('milleseconds not a number'); 
+    }
+
+    setTimeout(() => resolve("done!"), milliseconds)
+  });
+}
+
+module.exports = wait;