Fix version assignment in docker build script
Fix version assignment in docker build script

Docker builds were being versioned with literal '_version'
ninioe/traccar,orcoliver/traccar,ninioe/traccar,tananaev/traccar,orcoliver/traccar,ninioe/traccar,tsmgeek/traccar,jssenyange/traccar,jssenyange/traccar,jssenyange/traccar,tananaev/traccar,tsmgeek/traccar,jon-stumpf/traccar,jon-stumpf/traccar,tananaev/traccar,tsmgeek/traccar,orcoliver/traccar,jon-stumpf/traccar