Update .gitpod.Dockerfile

.gitpod.Dockerfile

@@ -1,5 +1,13 @@
 FROM gitpod/workspace-postgres
-# Install direnv
+ARG JULIA_URL="https://julialang-s3.julialang.org/bin/linux/x64/1.10/julia-1.10.3-linux-x86_64.tar.gz" 
+ARG JULIA_MINOR_VERSION="1.10"
+ARG JULIA_BUGFIX_VERSION="1.10.3"
+
 RUN sudo apt-get update && sudo apt-get install -y direnv \
-  && direnv hook bash >> /home/gitpod/.bashrc
+  && direnv hook bash >> /home/gitpod/.bashrc \
+  && echo "export PATH=/home/gitpod/julia/bin:$PATH" >> /home/gitpod/.bashrc
+RUN sudo curl -L "${JULIA_URL}" | tar -xzf - \
+  && mv julia-${JULIA_BUGFIX_VERSION} julia 
+RUN export PATH=/home/gitpod/julia/bin:$PATH \
+  && julia -e "using Pkg; Pkg.add(\"IJulia\")"