fix: keep OneSignal WorkManager workers in consumer R8 rules (#2585)

Co-authored-by: AR Abdul Azeez <[email protected]>

Author: abdulraqeeb33

OneSignalSDK/onesignal/notifications/consumer-rules.pro

@@ -54,4 +54,9 @@
 
 -keep class com.onesignal.JobIntentService$* {*;}
 
--keepclassmembers class com.onesignal.notifications.** { *; }
+-keepclassmembers class com.onesignal.notifications.** { *; }
+
+# Keep OneSignal WorkManager workers and constructors used for runtime instantiation.
+-keep class com.onesignal.notifications.internal.** extends androidx.work.ListenableWorker {
+    public <init>(android.content.Context, androidx.work.WorkerParameters);
+}