Hotfix to add missing rsync dependency when using the latest jupyter base image

docker-compose/jupyter/Dockerfile

@@ -16,6 +16,9 @@ RUN sudo apt-get install -y g++ gcc python3-dev
 # Install git to install pip requirements from git
 RUN sudo apt-get install -y git
 
+# Install dependencies of our scripts (bin/start-ds.sh)
+RUN sudo apt-get install -y rsync
+
 COPY requirements.txt ./
 RUN sudo pip3 install -r requirements.txt