Replaced ObjectsSubscription import with Subscription as per requirement

Author: sacOO7

lib/src/main/java/io/ably/lib/object/RealtimeObject.java

@@ -3,7 +3,6 @@
 import io.ably.lib.object.path.types.LiveMapPathObject;
 import io.ably.lib.object.state.ObjectStateChange;
 import io.ably.lib.object.state.ObjectStateEvent;
-import io.ably.lib.objects.ObjectsSubscription;
 import io.ably.lib.types.AblyException;
 import io.ably.lib.types.ErrorInfo;
 import org.jetbrains.annotations.Blocking;
@@ -69,7 +68,7 @@ private Unavailable() {}
         }
 
         @Override
-        public ObjectsSubscription on(@NotNull ObjectStateEvent event, ObjectStateChange.@NotNull Listener listener) {
+        public Subscription on(@NotNull ObjectStateEvent event, ObjectStateChange.@NotNull Listener listener) {
             throw missing();
         }
 

lib/src/main/java/io/ably/lib/object/state/ObjectStateChange.java

@@ -1,6 +1,6 @@
 package io.ably.lib.object.state;
 
-import io.ably.lib.objects.ObjectsSubscription;
+import io.ably.lib.object.Subscription;
 import org.jetbrains.annotations.NonBlocking;
 import org.jetbrains.annotations.NotNull;
 
@@ -17,7 +17,7 @@ public interface ObjectStateChange {
      * @return a subscription object that can be used to unsubscribe from the event
      */
     @NonBlocking
-    ObjectsSubscription on(@NotNull ObjectStateEvent event, @NotNull ObjectStateChange.Listener listener);
+    Subscription on(@NotNull ObjectStateEvent event, @NotNull ObjectStateChange.Listener listener);
 
     /**
      * Unsubscribes the specified listener from all synchronization state events.