Update backup script

nixos/common/software/cli/scripts/btrfs-backup.sh

@@ -75,7 +75,7 @@ Arguments:
 Environment:
     GOTIFY_TOKEN     Read from /run/secrets/btrfs-backups/gotify_token
     REMOTE_HOST      Default: root@synology
-    KEEP_SNAPSHOTS   Default: 14
+    KEEP_SNAPSHOTS   Default: 7
 
 Example:
     $(basename "$0") root
@@ -91,7 +91,7 @@ fi
 
 # Configurable variables (can be overridden by environment)
 : "${REMOTE_HOST:=root@synology}"
-: "${KEEP_SNAPSHOTS:=14}"
+: "${KEEP_SNAPSHOTS:=7}"
 : "${BACKUP_DESCRIPTION:=btrfs-backup}"
 
 # Configuration