Add missing package

Author: hdiethelm

.github/docker/Dockerfile

@@ -4,7 +4,7 @@ FROM $BASE_IMAGE
 
 #Install base dependencys
 RUN apt-get update
-RUN apt-get install -y devscripts equivs build-essential lintian clang git lsb-release python3 gpg sudo --no-install-recommends
+RUN apt-get install -y devscripts equivs build-essential lintian clang git lsb-release python3 gpg sudo xauth --no-install-recommends
 
 #Install linuxcnc dependencys
 #We need only the debian folder