Fix compose

• For mongo service, change the "sleep 3" instruction into "mongostat -n 1". The instruction meant to wait for the server startup procedure. Mongostat should print up when such procedure are completed meanwhile "sleep" is infrastucture dependent
  • For opensilex service, reply the "chown" command at the entry point time. The mounted volume remaind owned by root:root otherwise and the config file could not be generated. (Not reproduced)