Rpm: add test-rpm-barebones with Openbox

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builder/test-rpm-barebones

@@ -11,4 +11,5 @@ docker build --build-arg KASMVNC_PACKAGE_DIR="build" \
   -f dockerfile.${os}_${os_codename}.barebones.rpm.test .
 echo
 echo "You will be asked to set password. User name is docker."
-docker run -it -p 443:8443 --rm kasmvnctester_barebones_${os}:$os_codename
+docker run -it -p 443:8443 --rm -e "VNC_USER=foo" -e "VNC_PW=bar" \
+  kasmvnctester_barebones_${os}:$os_codename