Fix test bug where fixtures kept getting regenerated

Mistake in fa255c1.

Author: lawrence-forooghian

Tests/AblyLiveObjectsTests/JS Integration Tests/ObjectsIntegrationTests.swift

@@ -226,6 +226,7 @@ private actor ObjectsFixturesTrait: SuiteTrait, TestScoping {
                     try await helper.initForChannel(objectsFixturesChannel)
                 }
             }
+            self.setupTask = setupTask
 
             try await setupTask.value
         }