refactor(ivy): revert onChanges change back to a feature (#28187)

- adds fixmeIvy annotation to tests that should remain updated so we can resolve those issues in the subsequent commits

PR Close #28187

packages/core/test/linker/change_detection_integration_spec.ts

@@ -536,6 +536,7 @@ const TEST_COMPILER_PROVIDERS: Provider[] = [
              expect(renderLog.log).toEqual(['someProp=Megatron']);
            }));
 
+        fixmeIvy('FW-956: refactor onChanges').
         it('should record unwrapped values via ngOnChanges', fakeAsync(() => {
              const ctx = createCompFixture(
                  '<div [testDirective]="\'aName\' | wrappedPipe" [a]="1" [b]="2 | wrappedPipe"></div>');
@@ -738,6 +739,7 @@ const TEST_COMPILER_PROVIDERS: Provider[] = [
       });
 
       describe('ngOnChanges', () => {
+        fixmeIvy('FW-956: refactor onChanges').
         it('should notify the directive when a group of records changes', fakeAsync(() => {
              const ctx = createCompFixture(
                  '<div [testDirective]="\'aName\'" [a]="1" [b]="2"></div><div [testDirective]="\'bName\'" [a]="4"></div>');