docker: remove healthcheck against the SSH port (#6742)

Dockerfile

@@ -47,6 +47,6 @@ RUN ./docker/finalize.sh
 # Configure Docker Container
 VOLUME ["/data", "/backup"]
 EXPOSE 22 3000
-HEALTHCHECK CMD (nc -z -w 3 localhost 22 && curl -o /dev/null -sS http://localhost:3000/healthcheck) || exit 1
+HEALTHCHECK CMD (curl -o /dev/null -sS http://localhost:3000/healthcheck) || exit 1
 ENTRYPOINT ["/app/gogs/docker/start.sh"]
 CMD ["/bin/s6-svscan", "/app/gogs/docker/s6/"]