Remove the local jquery-1.9.1.min.js.

js/tests/index.html

@@ -12,9 +12,9 @@
         // get jquery param from the query string.
         var jQueryVersion = location.search.match(/[?&]jquery=(.*?)(?=&|$)/)
 
-        // If a version was specified, use that version from our vendor folder
+        // If a version was specified, use that version from jQuery CDN
         if (jQueryVersion) {
-          path = 'vendor/jquery-' + jQueryVersion[1] + '.min.js'
+          path = 'https://code.jquery.com/jquery-' + jQueryVersion[1] + '.min.js'
         }
         document.write('<script src="' + path + '"><\/script>')
       }())

js/tests/karma.conf.js

@@ -4,7 +4,7 @@ const path = require('path')
 const jsCoveragePath = path.resolve(__dirname, '../coverage')
 
 module.exports = (config) => {
-  const jqueryFile = process.env.USE_OLD_JQUERY ? 'js/tests/vendor/jquery-1.9.1.min.js' : 'assets/js/vendor/jquery-slim.min.js'
+  const jqueryFile = process.env.USE_OLD_JQUERY ? 'https://code.jquery.com/jquery-1.9.1.min.js' : 'assets/js/vendor/jquery-slim.min.js'
 
   config.set({
     basePath: '../..',