chore: remove phantomjs since it is deprecated

tests/run.js

@@ -1,24 +0,0 @@
-/**
- * Test Runner for Mocha tests
- * Using phantomjs to render page and execute scripts
- */
-
-var node_modules = '../node_modules/';
-phantom.injectJs(node_modules + 'mocha/mocha.js');
-phantom.injectJs(node_modules + 'sinon-chrome/src/phantom-tweaks.js');
-mocha.setup({ ui: 'bdd', reporter: 'spec' });
-
-// Setup
-phantom.injectJs('beforeeach.js');
-
-// Tests
-phantom.injectJs('..' + '/helpers/changeExtensionTooltip.spec.js');
-
-// Execute
-mocha.run(function (failures) {
-  // setTimeout is needed to supress "Unsafe JavaScript attempt to access..."
-  // see https://github.com/ariya/phantomjs/issues/12697
-  setTimeout(function () {
-    phantom.exit(failures);
-  }, 0);
-});