fix(filebrowser): define port based on env

compose/filebrowser/.env.example

@@ -1,3 +1,4 @@
+PORT="10943"
 DATA_PATH="/path/to/your/data"
 CONFIG_PATH="../../volumes/filebrowser"
 FB_BASEURL="/"

compose/filebrowser/docker-compose.yml

@@ -4,7 +4,7 @@ services:
     container_name: filebrowser
     user: "1000:1000"
     ports:
-      - "10943:8080"
+      - "${PORT:-10943}:8080"
     volumes:
       - "${DATA_PATH:?}:/data"
       - "${CONFIG_PATH:?}:/config"