change group declaration

Dockerfile

@@ -4,10 +4,6 @@ USER root
 
 RUN apk add --no-cache openssh-client git docker-cli docker-cli-compose
 
-RUN addgroup -g 996 docker || true
-
 RUN adduser -D -u 1000 -g 1000 sirian
 
-RUN addgroup sirian docker
-
 USER 1000

docker-compose.yml

@@ -34,6 +34,8 @@ services:
     build: .
     restart: unless-stopped
     user: "1000:1000"
+    group_add:
+     - "996"
     environment:
      - GITEA_INSTANCE_URL=https://git.sirian.me
      - GITEA_RUNNER_REGISTRATION_TOKEN=${RUNNER_TOKEN}