docker: remove hard-wired GAP version

Author: james-d-mitchell

Dockerfile

@@ -4,7 +4,7 @@ MAINTAINER J. D. Mitchell <[email protected]>
 
 COPY --chown=1000:1000 . $HOME/digraphs
 
-RUN rm -rf $HOME/inst/gap-4.10.2/pkg/digraphs-* && mv $HOME/digraphs $HOME/inst/gap-4.10.2/pkg/ && cd $HOME/inst/gap-4.10.2/pkg/digraphs && ./autogen.sh && ./configure && make  
+RUN rm -rf $HOME/inst/gap-${GAP_VERSION}/pkg/digraphs-* && mv $HOME/digraphs $HOME/inst/gap-${GAP_VERSION}/pkg/ && cd $HOME/inst/gap-${GAP_VERSION}/pkg/digraphs && ./autogen.sh && ./configure && make  
 
 RUN sudo pip3 install ipywidgets RISE jupyter_francy
 
@@ -16,4 +16,4 @@ RUN sudo jupyter nbextension enable --user --py --sys-prefix jupyter_francy
 
 USER gap
 
-WORKDIR $HOME/inst/gap-4.10.2/pkg/digraphs/notebooks
+WORKDIR $HOME/inst/gap-${GAP_VERSION}/pkg/digraphs/notebooks