IAM manager doesn't need to check for onFocus in addition to onSessio…

…nStarted

* The onSessionStarted callback already will fetch messages.
* Now that session starting (including cold starts) should always trigger the subscribers, there is no need to also fetch messages within onFocus

OneSignalSDK/onesignal/in-app-messages/src/main/java/com/onesignal/inAppMessages/internal/InAppMessagesManager.kt

@@ -881,15 +881,7 @@ internal class InAppMessagesManager(
             .show()
     }
 
-    private var onFocusCalled: Boolean = false
-
-    override fun onFocus() {
-        if (onFocusCalled) return
-        onFocusCalled = true
-        suspendifyOnThread {
-            fetchMessages()
-        }
-    }
+    override fun onFocus() { }
 
     override fun onUnfocused() { }
 }