Use https for javascript file (#3012)

Author: jonathanmetzman

src/clusterfuzz/_internal/tests/appengine/javascripts/template.html

@@ -25,7 +25,7 @@
   <script src="https://cdn.rawgit.com/jquery/jquery/2.1.4/dist/jquery.min.js"></script>
   <script src="https://cdn.rawgit.com/Automattic/expect.js/0.3.1/index.js"></script>
   <script src="https://cdn.rawgit.com/mochajs/mocha/2.2.5/mocha.js"></script>
-  <script src="http://chaijs.com/chai.js"></script>
+  <script src="https://chaijs.com/chai.js"></script>
 
   <script>mocha.setup('bdd')</script>
   %s