feat: Allow passing null or undefined as the value for options in app.render (#6903)

* fix: allow null options in app.render

* fix: ensure options are initialized to an empty object in app.render

* docs: add history entry

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Co-authored-by: Sebastian Beltran <bjohansebas@gmail.com>

lib/application.js

@@ -523,7 +523,7 @@ app.render = function render(name, options, callback) {
   var cache = this.cache;
   var done = callback;
   var engines = this.engines;
-  var opts = options;
+  var opts = options || {};
   var view;
 
   // support callback function as second arg