chore(deps): pin mongo docker tag to 4f93a84 (#849)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

docker-compose.yml

@@ -15,7 +15,7 @@ services:
     depends_on:
       - db
   db:
-    image: mongo:8
+    image: mongo:8@sha256:4f93a84f7d4d8b1b6cb7e0c172d8a44b0bed9b399f207165ea19473bdb5a36b0
     restart: always
     volumes:
       - ./database:/data/db