revert: use port 2222 to avoid host SSH conflict

Dockerfile

@@ -24,7 +24,7 @@ RUN useradd -m shellmate && \
 USER shellmate
 RUN ssh-keygen -t ed25519 -f /etc/shellmate/ssh_host_key -N ""
 
-EXPOSE 22
+EXPOSE 2222
 
 ENV STOCKFISH_PATH=/usr/games/stockfish
 

docker-compose.yml

@@ -2,9 +2,9 @@ services:
   shellmate:
     build: .
     ports:
-      - "22:22"
+      - "2222:2222"
     environment:
-      - SHELLMATE_SSH_PORT=22
+      - SHELLMATE_SSH_PORT=2222
       - SHELLMATE_REDIS_URL=redis://redis:6379
       - SHELLMATE_DATABASE_URL=postgresql://shellmate:shellmate@postgres:5432/shellmate
       - STOCKFISH_PATH=/usr/games/stockfish
@@ -13,7 +13,7 @@ services:
       - postgres
     restart: unless-stopped
     healthcheck:
-      test: ["CMD", "nc", "-z", "localhost", "22"]
+      test: ["CMD", "nc", "-z", "localhost", "2222"]
       interval: 30s
       timeout: 10s
       retries: 3