fix(amplify_push_notifications): replace removeFirst() with removeAt(0) for Android < 11 compatibility

The removeFirst() method from the Kotlin standard library is only available on
Android 11 (API 30) and above, or when running on a full Java 11+ runtime.
On older Android versions, this causes a NoSuchMethodError at runtime.

This commit replaces removeFirst() with removeAt(0), which provides the same
behavior and works correctly on all supported Android API levels (minSdk 21+).

No functional behavior changes have been made — only improved runtime
compatibility.

Author: LucasNovaes

packages/notifications/push/amplify_push_notifications/android/src/main/kotlin/com/amazonaws/amplify/amplify_push_notifications/PushNotificationEventsStreamHandler.kt

@@ -102,7 +102,7 @@ class PushNotificationEventsStreamHandler constructor(
         try {
             eventSink?.let {
                 while (eventQueue.isNotEmpty()) {
-                    val eventFromQueue = eventQueue.removeFirst()
+                    val eventFromQueue = eventQueue.removeAt(0)
                     // Check if it is an Error event and handle accordingly by using .error method
                     if (eventFromQueue.event.eventName == NativeEvent.ERROR.eventName) {
                         val exception = eventFromQueue.error