switch GCR -> Artifact-Registry

GCR has been deprecated [0] in favour of Artifact-Registry.

Thus, change push-targets for OCI-Images:

- europe-docker.pkg.dev/gardener-project/snapshots for snapshots
- europe-docker.pkg.dev/gardener-project/releases for releases
- europe-docker.pkg.dev/gardener-project/public for read-access to
  snapshots + releases

[0]
https://cloud.google.com/artifact-registry/docs/transition/transition-from-gcr

.ci/pipeline_definitions

@@ -4,12 +4,13 @@ machine-controller-manager-provider-openstack:
       version:
         preprocess: 'inject-commit-hash'
         inject_effective_version: true
-      component_descriptor: ~
+      component_descriptor:
+        ocm_repository: europe-docker.pkg.dev/gardener-project/snapshots
       publish:
         dockerimages:
           machine-controller-manager-provider-openstack:
             dockerfile: 'Dockerfile'
-            image: 'eu.gcr.io/gardener-project/gardener/machine-controller-manager-provider-openstack'
+            image: europe-docker.pkg.dev/gardener-project/snapshots/gardener/machine-controller-manager-provider-openstack
             target: machine-controller
             resource_labels:
             - name: 'gardener.cloud/cve-categorisation'
@@ -30,17 +31,26 @@ machine-controller-manager-provider-openstack:
             image_reference: 'golang:1.20.5'
     head-update:
       traits:
+        component_descriptor:
+          ocm_repository_mappings:
+            - repository: europe-docker.pkg.dev/gardener-project/releases
         draft_release: ~
     pull-request:
       traits:
         pull-request: ~
+        component_descriptor:
+          ocm_repository_mappings:
+            - repository: europe-docker.pkg.dev/gardener-project/releases
     release:
       traits:
         version:
           preprocess: 'finalize'
+        component_descriptor:
+          ocm_repository: europe-docker.pkg.dev/gardener-project/releases
         release:
           nextversion: 'bump_minor'
         publish:
           dockerimages:
             machine-controller-manager-provider-openstack:
               tag_as_latest: true
+              image: europe-docker.pkg.dev/gardener-project/releases/gardener/machine-controller-manager-provider-openstack

Makefile

@@ -9,8 +9,8 @@ BINARY_PATH         := bin/
 REPO_ROOT           := $(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
 HACK_DIR            := $(REPO_ROOT)/hack
 COVERPROFILE        := test/output/coverprofile.out
-REGISTRY            := eu.gcr.io/gardener-project/gardener
-IMAGE_PREFIX        := $(REGISTRY)/extensions
+REGISTRY            := europe-docker.pkg.dev/gardener-project/public
+IMAGE_PREFIX        := $(REGISTRY)/gardener/extensions
 NAME                := machine-controller-manager-provider-openstack
 IMAGE_NAME          := $(IMAGE_PREFIX)/$(NAME)
 VERSION             := $(shell cat VERSION)

kubernetes/deployment.yaml

@@ -20,7 +20,7 @@ spec:
     spec:
       containers:
       - name: machine-controller-manager
-        image: eu.gcr.io/gardener-project/gardener/machine-controller-manager:v0.42.0
+        image: europe-docker.pkg.dev/gardener-project/public/gardener/machine-controller-manager:v0.42.0
         imagePullPolicy: Always
         command:
           - ./machine-controller-manager