ci: always cleanup pip and cargo leftovers

This is leftovers from the compilation/installation phase.

In the build containers this took around ~ 400 MB.

Reviewed-by: Martin Roukala <martin.roukala@mupuf.org>
Signed-off-by: David Heidelberg <david.heidelberg@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25843>

.gitlab-ci/container/container_post_build.sh

@@ -1,10 +1,12 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 if test -f /etc/debian_version; then
     apt-get autoremove -y --purge
 fi
 
-# Clean up any build cache for rust.
+# Clean up any build cache
+rm -rf /root/.cache
+rm -rf /root/.cargo
 rm -rf /.cargo
 
 if test -x /usr/bin/ccache; then

.gitlab-ci/container/debian/x86_64_test-base.sh

@@ -150,11 +150,9 @@ pip3 install --break-system-packages yq
 ############### Build dEQP runner
 . .gitlab-ci/container/build-deqp-runner.sh
 
-rm -rf /root/.cargo
-rm -rf /root/.rustup
-
-ccache --show-stats
 
 apt-get purge -y $STABLE_EPHEMERAL
 
-apt-get autoremove -y --purge
+rm -rf /root/.rustup
+
+. .gitlab-ci/container/container_post_build.sh