generalize backup instructions

* Backup apps are not lineage specific and oai supports different roms as well

Signed-off-by: SirRGB <sirrgb@proton.me>

Author: SirRGB

openandroidinstaller/views/welcome_view.py

@@ -74,7 +74,7 @@ def build(self):
 - you have a backup of all your important data, since this procedure will **erase all data from the phone**.
 - to not store the backup on the phone!
 
-Please note, that vendor specific back-ups will most likely not work on LineageOS!
+Please note, that vendor specific back-ups will most likely not work on LineageOS and other custom ROMs!
                 """
                 ),
                 Divider(),