ci: don't delete the apt cache Deleting the apt cache can be helpful for reducing the size of a container, but since we don't push it anywhere, it only hinders our ability to debug problems while working on the container. Keep it.
diff --git a/azure-pipelines/docker/xenial b/azure-pipelines/docker/xenial
index 74be1ac..108f5de 100644
--- a/azure-pipelines/docker/xenial
+++ b/azure-pipelines/docker/xenial
@@ -21,9 +21,7 @@ RUN echo 'deb http://ppa.launchpad.net/hola-launchpad/valgrind/ubuntu xenial mai
openssl \
pkgconf \
python \
- valgrind \
- && \
- rm -rf /var/lib/apt/lists/*
+ valgrind
RUN mkdir /var/run/sshd
RUN cd /tmp && \