Remove spy

It breaks the other tests.

Author: sebmarkbage

packages/react-dom/src/__tests__/ReactComponent-test.js

@@ -134,8 +134,6 @@ describe('ReactComponent', () => {
 
   // @gate !disableStringRefs
   it('string refs do not detach and reattach on every render', async () => {
-    spyOnDev(console, 'error').mockImplementation(() => {});
-
     let refVal;
     class Child extends React.Component {
       componentDidUpdate() {
@@ -174,6 +172,8 @@ describe('ReactComponent', () => {
       root.render(<Parent />);
     });
 
+    assertConsoleErrorDev(['contains the string ref']);
+
     expect(refVal).toBe(undefined);
     await act(() => {
       root.render(<Parent showChild={true} />);