feat: Request POST_NOTIFICATIONS permission in Android 13 and higher

[brosssh]

Feature description

POST_NOTIFICATIONS is required on Android 13+ else notifications wont show. A dialog asking for the permission is probably needed.

Motivation

.

Acknowledgements

• I have checked all open and closed feature requests and this is not a duplicate.
• I have chosen an appropriate title.
• The feature request is only related to ReVanced Manager.