Fix error message for invalid snapshot id in `fsck`
Fix error message for invalid snapshot id in `fsck`

fawick/restic,kurin/restic,bchapuis/restic,jayme-github/restic,middelink/restic,byo/restic,stuertz/restic,rakoo/restic,restic/restic,intfrr/restic,mappu/restic,ar-jan/restic,episource/restic,rakoo/restic,ar-jan/restic,kurin/restic,restic/restic,klauspost/restic,stuertz/restic,jayme-github/restic,arithmetric/restic,ckemper67/restic,howeyc/restic,pombredanne/restic,byo/restic,fawick/restic,middelink/restic