test: fix revokeObjectURL mock in export tests

Add conditional creation of window.URL.revokeObjectURL in test setup
since it doesn't exist in Jest's JSDOM environment. This prevents
'Property revokeObjectURL does not exist' errors during test execution.

Author: eschutho

superset-frontend/src/utils/export.test.ts

@@ -74,15 +74,20 @@ beforeEach(() => {
   createObjectURLSpy = jest
     .spyOn(window.URL, 'createObjectURL')
     .mockReturnValue('blob:mock-url');
-  revokeObjectURLSpy = jest
-    .spyOn(window.URL, 'revokeObjectURL')
-    .mockImplementation(() => {});
+
+  // Create revokeObjectURL if it doesn't exist
+  if (!window.URL.revokeObjectURL) {
+    window.URL.revokeObjectURL = jest.fn();
+  }
+  revokeObjectURLSpy = jest.spyOn(window.URL, 'revokeObjectURL');
 });
 
 afterEach(() => {
   createElementSpy.mockRestore();
   createObjectURLSpy.mockRestore();
-  revokeObjectURLSpy.mockRestore();
+  if (revokeObjectURLSpy) {
+    revokeObjectURLSpy.mockRestore();
+  }
 });
 
 test('exports resource with correct endpoint and headers', async () => {