Images in _static folder can only be viewed from GH Pages, not when run locally

See commit https://github.com/robocup-junior/onstage/commit/0643b1a50c7babf701e0de8fbdf35298400afa7f 

Need to fix either the location of the file or the link to it. Currently the link is not working, when running a local webserver because of the /onstage/ that directs github pages to the correct file location.