Remove unused method

This used to be an override of a method in the base class, but that method is long gone...

lib/commands/test.js

@@ -10,18 +10,6 @@ module.exports = TestCommand.extend({
 
   availableOptions: buildAvailableOptions(),
 
-  rmTmp() {
-    if (process.platform === 'win32') {
-      // There is some kind of race condition where we intermittently get EBUSY
-      // deleting the temp directory on windows, which causes the test to fail.
-      // Unfortunately adding logging to try to track it down makes it go away,
-      // so let's just delay for a bit as a dirty workaround.
-      require('child_process').execSync('ping 127.0.0.1 -n 2 > nul');
-    }
-
-    return this._super(...arguments);
-  },
-
   async run(commandOptions) {
     let _super = this._super;
     await prepareRunCommand(this.project);