test: reset counters before running a styling test (#45670)

This commit updates one of the styling tests to reset perf counters, making it order-independent and non-flaky (previously the test got random failures depending on whether there are other tests invoked before).

PR Close #45670

packages/core/test/render3/instructions/styling_spec.ts

@@ -97,6 +97,7 @@ describe('styling', () => {
   });
 
   it('should set class based on priority', () => {
+    ngDevModeResetPerfCounters();
     ɵɵclassProp('foo', false);
     ɵɵclassProp('foo', true);  // Higher priority, should win.
     expectClass(div).toEqual({foo: true});