Bug with sshd (#1297)

* Workaround for a bug with sshd

* Update containers/sandbox/Dockerfile

Co-authored-by: Engel Nyst <enyst@users.noreply.github.com>

---------

Co-authored-by: Xingyao Wang <xingyao6@illinois.edu>

containers/sandbox/Dockerfile

@@ -18,5 +18,7 @@ RUN apt-get update && apt-get install -y \
     sudo \
     && rm -rf /var/lib/apt/lists/*
 
+RUN mkdir -p -m0755 /var/run/sshd
+
 # symlink python3 to python
 RUN ln -s /usr/bin/python3 /usr/bin/python