[fix] hook_exec / subprocess.Popen explodes if you feed non-string values in env variables
[fix] hook_exec / subprocess.Popen explodes if you feed non-string values in env variables

YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/yunohost,YunoHost/yunohost,YunoHost/moulinette-yunohost,YunoHost/yunohost,YunoHost/yunohost