ci/lava: Add LAVA SSH client container

- To keep things organized, create a base hidden jobs for alpine images,
  as we have 2 now
- This image will have an SSH client ran by LAVA dispatchers
  (x86_64-only) who will serve as a bypass channel of output and dmesg
  and an alternative for UART.

Signed-off-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23534>

.gitlab-ci/container/alpine/x86_64_lava_ssh_client.sh

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+
+# This is a ci-templates build script to generate a container for LAVA SSH client.
+
+# shellcheck disable=SC1091
+set -e
+set -o xtrace
+
+EPHEMERAL=(
+)
+
+# We only need these very basic packages to run the tests.
+DEPS=(
+    openssh-client  # for ssh
+    iputils         # for ping
+    bash
+    curl
+)
+
+
+apk add "${DEPS[@]}" "${EPHEMERAL[@]}"
+
+. .gitlab-ci/container/container_pre_build.sh
+
+############### Uninstall the build software
+
+apk del "${EPHEMERAL[@]}"
+
+. .gitlab-ci/container/container_post_build.sh

.gitlab-ci/container/gitlab-ci.yml

@@ -276,12 +276,18 @@ debian/arm64_build:
 
 
 # Alpine based x86_64 build image
-alpine/x86_64_build:
+.alpine/x86_64_build-base:
   extends:
     - .fdo.container-build@alpine
     - .container
   variables:
     FDO_DISTRIBUTION_VERSION: "3.18"
+
+# Alpine based x86_64 build image
+alpine/x86_64_build:
+  extends:
+    - .alpine/x86_64_build-base
+  variables:
     MESA_IMAGE_TAG: &alpine-x86_64_build ${ALPINE_X86_64_BUILD_TAG}
 
 .use-alpine/x86_64_build:
@@ -293,6 +299,13 @@ alpine/x86_64_build:
   needs:
     - alpine/x86_64_build
 
+# Alpine based x86_64 image for LAVA SSH dockerized client
+alpine/x86_64_lava_ssh_client:
+  extends:
+    - .alpine/x86_64_build-base
+  variables:
+    MESA_IMAGE_TAG: &alpine-x86_64_lava_ssh_client ${ALPINE_X86_64_LAVA_SSH_TAG}
+
 # Fedora based x86_64 build image
 fedora/x86_64_build:
   extends: