Update xl.Dockerfile

containers/jug/xl.Dockerfile

@@ -83,7 +83,7 @@ RUN cd /tmp
  && popd                                                                        \
  && rm -rf build ip6                                                            \
  && echo "ADDING SETUP SCRIPT"                                                  \
- && echo 'export $LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/detector/lib'           \
+ && echo 'export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/detector/lib'           \
          > /opt/detector/setup.sh
 
 ## Install benchmarks into the container