Add missing flavors

lib/android/app/src/reactNative59/java/com/wix/reactnativenotifications/NotificationManagerCompatFacade.java

+
+package com.wix.reactnativenotifications;
+
+import android.content.Context;
+import android.support.annotation.Nullable;
+import android.support.v4.app.NotificationManagerCompat;
+
+public abstract class NotificationManagerCompatFacade {
+    public static NotificationManagerCompat from(@NonNull Context context) {
+        return NotificationManagerCompat.from(context);
+    }
+}

lib/android/app/src/reactNative60/java/com/wix/reactnativenotifications/NotificationManagerCompatFacade.java

+
+package com.wix.reactnativenotifications;
+
+import android.content.Context;
+import androidx.annotation.NonNull;
+import androidx.core.app.NotificationManagerCompat;
+
+public abstract class NotificationManagerCompatFacade {
+    public static NotificationManagerCompat from(@NonNull Context context) {
+        return NotificationManagerCompat.from(context);
+    }
+}