Move sql file for `remove_deleted_devices_from_device_inbox` into v65 (#11303)

changelog.d/11303.misc

@@ -0,0 +1 @@
+Fix an issue which prevented the 'remove deleted devices from device_inbox column' background process from running when updating from a recent Synapse version.

synapse/storage/schema/main/delta/65/05remove_deleted_devices_from_device_inbox.sql

@@ -19,4 +19,4 @@
 -- This runs as background task, but may take a bit to finish.
 
 INSERT INTO background_updates (ordering, update_name, progress_json) VALUES
-  (6402, 'remove_deleted_devices_from_device_inbox', '{}');
+  (6505, 'remove_deleted_devices_from_device_inbox', '{}');