Bring it up to parity with the LAVA and bare-metal containers by
stripping things we don't need at runtime. There is a lot of stuff we
don't need in container images we only use to execute tests, including
but not limited to the system Mesa which can only cause problems. Call
the same strip-rootfs we already run for LAVA to make sure that this
doesn't happen, as well as slimming down the container image.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31281>
