The plots of the test results aren't shown anymore
In the xslt file there are links to plots but they seem to be missing. This worked on 11-11-2019 but a day later not anymore.
Commit 4a16a71d seem to introduce this bug.
If I try to manually load the graphics file (e.g. http://amas.web.psi.ch/opal/regressionTests/master/plots_2020-05-15/AWAGun-1_rms_x.png) then I get the message 'Die Graphik "http://amas.web.psi.ch/opal/regressionTests/master/plots_2020-05-15/AWAGun-1_rms_x.png" kann nicht angezeigt werden, weil sie Fehler enthaelt'.