Removed only and added comment

Author: maneesht

packages/database/test/exp/integration.test.ts

@@ -120,7 +120,11 @@ describe('Database@exp Tests', () => {
     unsubscribe();
   });
 
-  it.only('can properly handle unknown deep merges', async () => {
+  it('can properly handle unknown deep merges', async () => {
+    // Note: This test requires `testIndex` to be added as an index.
+    // Without an index, the test will erroneously pass.
+    // But we are unable to add indexes on the fly to the actual db, so 
+    // running on the emulator is the best way to test this.
     const database = getDatabase(defaultApp);
     const root = ref(database, 'testing');
     await set(root, {});