update dockerfile to discard package repo cache

Author: akerl

Dockerfile

@@ -6,6 +6,6 @@ ADD cert /tmp/ducktape/cert
 ADD https://github.com/dock0/ducktape/releases/download/$DUCKTAPE_VERSION/ducktape /tmp/ducktape/ducktape
 RUN ["/tmp/ducktape/shim", ""]
 RUN ["/tmp/ducktape/ducktape", "https://github.com/dock0/tarball_arch/releases/download/v2.0.1/root.tar.bz2"]
-RUN pacman -Sy --needed --noconfirm archlinux-keyring
+RUN pacman -Syy --needed --noconfirm archlinux-keyring
 RUN pacman -Syu --needed --noconfirm git iproute2 iputils procps-ng tar which licenses util-linux
 CMD ["/bin/bash"]

scripts/test.sh

@@ -3,4 +3,4 @@
 set -euo pipefail
 
 docker run -i new /bin/bash --version
-docker run -i new pacman -Syu --noconfirm make
+docker run -i new pacman -S --noconfirm make