[minor bugfix] fix minor bug with handleReset in suspense fixture (#13843)

* fix minor bug with handleReset in suspense fixture

otherwise resetting the cache in debugger throws an error 

reported here
https://www.reddit.com/r/reactjs/comments/9n9nfo/react_166_canary/

* fix singlequote/doublequote

* switch to performance.now()

fixtures/unstable-async/suspense/src/index.js

@@ -65,7 +65,7 @@ class Debugger extends PureComponent {
   }
 
   handleReset = () => {
-    trace('Clear cache', () => {
+    trace('Clear cache', performance.now(), () => {
       cache.invalidate();
       this.setState(state => ({
         requests: {},