mount tmpfs for apt caches

Author: featheredtoast

image/base/Dockerfile

@@ -69,6 +69,8 @@ RUN echo 2.0.`date +%Y%m%d` > /VERSION
 RUN echo "deb http://deb.debian.org/debian ${DEBIAN_RELEASE}-backports main" > "/etc/apt/sources.list.d/${DEBIAN_RELEASE}-backports.list"
 
 RUN --mount=type=tmpfs,target=/var/log \
+  --mount=type=tmpfs,target=/var/cache/apt \
+  --mount=type=tmpfs,target=/var/lib/apt \
     echo "debconf debconf/frontend select Teletype" | debconf-set-selections; \
     apt-get -y update && DEBIAN_FRONTEND=noninteractive apt-get -y install gnupg sudo curl fping locales \
     ca-certificates rsync \