ci: docker-compose: Add MOUNT_ACCESS_MODE variable (#42238)

Add a `MOUNT_ACCESS_MODE` variable to set mount options
on the volumes. Environments where SELinux is enabled will now be able
to mount to the volumes with `MOUNT_ACCESS_MODE=":Z"` to make the bind
mount permissions work correctly.

It now compiles on Fedora 43 with `MOUNT_ACCESS_MODE=":Z"`.

Should have no impact in envs where MOUNT_ACCESS_MODE is not set (haven't
tested myself).

Fixes: #42197

Signed-off-by: Guillaume Champagne <[email protected]>

Author: gchamp20

ci/docker-compose.yml

@@ -92,9 +92,9 @@ services:
   envoy-build:
     <<: *envoy-build-base
     volumes:
-    - ${ENVOY_DOCKER_BUILD_DIR:-/tmp/envoy-docker-build}:/build
-    - ${SOURCE_DIR:-..}:/source
-    - ${SHARED_TMP_DIR:-/tmp/bazel-shared}:${SHARED_TMP_DIR:-/tmp/bazel-shared}
+    - ${ENVOY_DOCKER_BUILD_DIR:-/tmp/envoy-docker-build}:/build${MOUNT_ACCESS_MODE:-}
+    - ${SOURCE_DIR:-..}:/source${MOUNT_ACCESS_MODE:-}
+    - ${SHARED_TMP_DIR:-/tmp/bazel-shared}:${SHARED_TMP_DIR:-/tmp/bazel-shared}${MOUNT_ACCESS_MODE:-}
 
   envoy-build-gpg:
     <<: *envoy-build-base