fix(kaniko): force '--cache-repo' option (strip tag)

Workaround for https://github.com/GoogleContainerTools/kaniko/issues/1459

templates/gitlab-ci-docker.yml

@@ -384,7 +384,7 @@ stages:
 
   function create_kaniko_cache_dir() {
     # create cache directory if needed
-      mkdir -p "$KANIKO_CACHE_DIR"
+    mkdir -p "${CI_PROJECT_DIR}/.cache"
   }
 
   function init_workspace() {
@@ -416,6 +416,7 @@ stages:
 
   function run_build_kaniko() {
     docker_image=$1
+    kaniko_registry_repository=$(echo "$DOCKER_SNAPSHOT_IMAGE" | cut -d: -f1)
     shift
     if [[ -n "$DOCKER_REGISTRY_MIRROR" ]]
     then
@@ -423,9 +424,9 @@ stages:
       kaniko_registry_mirror_option="--registry-mirror $(echo ${DOCKER_REGISTRY_MIRROR} | sed "s|^https*://||")"
     fi
     log_info "Build & deploy image $docker_image"
-    log_info "Kaniko command: /kaniko/executor --context $(docker_context_path) --dockerfile $DOCKER_FILE --destination $docker_image --cache --cache-dir=$KANIKO_CACHE_DIR --verbosity $DOCKER_KANIKO_VERBOSITY $kaniko_registry_mirror_option $DOCKER_METADATA $DOCKER_BUILD_ARGS $*"
+    log_info "Kaniko command: /kaniko/executor --context $(docker_context_path) --dockerfile $DOCKER_FILE --destination $docker_image --cache --cache-dir=${CI_PROJECT_DIR}/.cache --cache-repo="$kaniko_registry_repository" --verbosity $DOCKER_KANIKO_VERBOSITY $kaniko_registry_mirror_option $DOCKER_METADATA $DOCKER_BUILD_ARGS $*"
     # shellcheck disable=SC2086
-    /kaniko/executor --context "$(docker_context_path)" --dockerfile "$DOCKER_FILE" --destination "$docker_image" --cache --cache-dir="$KANIKO_CACHE_DIR" --verbosity $DOCKER_KANIKO_VERBOSITY $kaniko_registry_mirror_option $DOCKER_METADATA $DOCKER_BUILD_ARGS "$@"
+    /kaniko/executor --context "$(docker_context_path)" --dockerfile "$DOCKER_FILE" --destination "$docker_image" --cache --cache-dir="${CI_PROJECT_DIR}/.cache" --cache-repo="$kaniko_registry_repository" --verbosity $DOCKER_KANIKO_VERBOSITY $kaniko_registry_mirror_option $DOCKER_METADATA $DOCKER_BUILD_ARGS "$@"
   }
 
   # Used by containers tools like buildah, skopeo.
@@ -456,7 +457,6 @@ stages:
     name: "$DOCKER_KANIKO_IMAGE"
     entrypoint: [""]
   variables:
-    KANIKO_CACHE_DIR: "${CI_PROJECT_DIR}/.cache"
     BUILDTOOL_HOME: "/kaniko"
   cache:
     key: "$CI_COMMIT_REF_SLUG-docker"