Remove the perform backup tasks flag.

This flag is now abandoned and will not be used in the future.

Bug: 382295619
Test: builds
Flag: EXEMPT removing com.android.settings.flags.enable_perform_backup_tasks_in_settings
Change-Id: I1aa162145b09f18ad0cc8d16d96dbd6d07b149a9
diff --git a/aconfig/settings_perform_backup_tasks_flag_declarations.aconfig b/aconfig/settings_perform_backup_tasks_flag_declarations.aconfig
deleted file mode 100644
index dcb876b..0000000
--- a/aconfig/settings_perform_backup_tasks_flag_declarations.aconfig
+++ /dev/null
@@ -1,9 +0,0 @@
-package: "com.android.settings.flags"
-container: "system_ext"
-
-flag {
-  name: "enable_perform_backup_tasks_in_settings"
-  namespace: "backstage_power"
-  description: "Enable the Perform Backup Tasks screen in Settings"
-  bug: "320563660"
-}