fix: set mongodb version to 6 (#170)

docker-compose.prod.yml

@@ -54,7 +54,7 @@ services:
       - .env
 
   db:
-    image: mongo
+    image: mongo:6
     restart: always
     networks:
       - internal

docker-compose.yml

@@ -1,7 +1,7 @@
 version: '3'
 services:
   db:
-    image: mongo
+    image: mongo:6
     restart: always
     networks:
       - internal

server/src/config.ts

@@ -101,6 +101,7 @@ function getProjectRoot(): string {
 const config = createConfig()
 
 export function getQuestImage(id: string): string {
+  // TODO: handle staging images (add version tag)
   return `${config.docker.imagePrefix}${id}`
 }