Joined Cases C-529/21, C-530/21, C-531/21, C-532/21, C-533/21, C-534/21, C-535/21 and С-536/21: Request for a preliminary ruling from the Rayonen sad — Kula (Bulgaria) lodged on 25 August 2021 — OP, MN, KL, IJ, GH, EF, CD and AB v Glavna direktsia ‘Pozharna bezopasnost i zashtita na naselenieto’ kam Ministerstvo na vatreshnite raboti