style: convert environment variables to key-value pairs

gitea/compose.yaml

@@ -8,8 +8,8 @@ services:
       - /etc/timezone:/etc/timezone:ro
       - /etc/localtime:/etc/localtime:ro
     environment:
-      - USER_UID=1000
-      - USER_GID=1000
+      USER_UID: "1000"
+      USER_GID: "1000"
     networks:
       - proxy
     restart: unless-stopped