scripted-diff: ci: Rework docker naming

DOCKER in names is confusingly used as synonym for "image", "container",
and "ci". Fix the confusion by picking the term that fits the context.

-BEGIN VERIFY SCRIPT-
 ren() { sed -i "s:$1:$2:g" $( git grep -l "$1" ) ; }

 ren DOCKER_PACKAGES CI_BASE_PACKAGES
 # This better reflects that they are the common base for all CI
 # containers.

 ren DOCKER_ID CI_CONTAINER_ID
 # This is according to the documentation of "--detach , -d: Run
 # container in background and print container ID".

 ren DOCKER_NAME_TAG CI_IMAGE_NAME_TAG
 # This avoids confusing with CONTAINER_NAME and clarifies that it is an
 # image.

 ren DOCKER_ADMIN CI_CONTAINER_CAP
 # This clarifies that it is a capability added to the container.

 ren DOCKER_CI_CMD_PREFIX CI_EXEC_CMD_PREFIX
 # This brings it in line with the CI_EXEC naming.

-END VERIFY SCRIPT-

ci/test/00_setup_env_native_msan.sh

@@ -6,7 +6,7 @@
 
 export LC_ALL=C.UTF-8
 
-export DOCKER_NAME_TAG="ubuntu:20.04"
+export CI_IMAGE_NAME_TAG="ubuntu:20.04"
 LIBCXX_DIR="${BASE_SCRATCH_DIR}/msan/build/"
 export MSAN_FLAGS="-fsanitize=memory -fsanitize-memory-track-origins=2 -fno-omit-frame-pointer -g -O1 -fno-optimize-sibling-calls"
 LIBCXX_FLAGS="-nostdinc++ -stdlib=libc++ -L${LIBCXX_DIR}lib -lc++abi -I${LIBCXX_DIR}include -I${LIBCXX_DIR}include/c++/v1 -lpthread -Wl,-rpath,${LIBCXX_DIR}lib -Wno-unused-command-line-argument"