Remove all references to cluster-api-bootstrap-provider-kubeadmm

This repository has been inactive for a long time, and it's due for
archival.

Signed-off-by: Vince Prignano <vincepri@vmware.com>

config/jobs/image-pushing/k8s-staging-cluster-api.yaml

@@ -121,29 +121,6 @@ postsubmits:
               - --scratch-bucket=gs://k8s-staging-cluster-api-gcp-gcb
               - --env-passthrough=PULL_BASE_REF
               - .
-  kubernetes-sigs/cluster-api-bootstrap-provider-kubeadm:
-    - name: post-cluster-api-bootstrap-provider-push-images
-      cluster: k8s-infra-prow-build-trusted
-      annotations:
-        # this is the name of some testgrid dashboard to report to.
-        testgrid-dashboards: sig-cluster-lifecycle-image-pushes, wg-k8s-infra-gcb
-      decorate: true
-      branches:
-        - ^master$
-        # this is a regex for semver, from https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string
-        - ^v(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$
-      spec:
-        serviceAccountName: gcb-builder
-        containers:
-          - image: gcr.io/k8s-testimages/image-builder:v20210622-762366a
-            command:
-              - /run.sh
-            args:
-              # this is the project GCB will run in, which is the same as the GCR images are pushed to.
-              - --project=k8s-staging-capi-kubeadm
-              - --scratch-bucket=gs://k8s-staging-capi-kubeadm-gcb
-              - --env-passthrough=PULL_BASE_REF
-              - .
   kubernetes-sigs/cluster-api-provider-nested:
     - name: post-cluster-api-provider-nested-push-images
       cluster: k8s-infra-prow-build-trusted

config/prow/plugins.yaml

@@ -389,10 +389,6 @@ repo_milestone:
     maintainers_id: 3058957
     maintainers_team: cluster-api-maintainers
     maintainers_friendly_name: Cluster API Maintainers
-  kubernetes-sigs/cluster-api-bootstrap-provider-kubeadm:
-    maintainers_id: 3302228
-    maintainers_team: cluster-api-bootstrap-provider-kubeadm-maintainers
-    maintainers_friendly_name: Cluster API Bootstrap Provider Kubeadm Maintainers
   kubernetes-sigs/cluster-api-provider-aws:
     maintainers_id: 2830895
     maintainers_team: cluster-api-provider-aws-maintainers
@@ -1062,10 +1058,6 @@ plugins:
     - milestone
     - override
 
-  kubernetes-sigs/cluster-api-bootstrap-provider-kubeadm:
-    plugins:
-    - milestone
-
   kubernetes-sigs/image-builder:
     plugins:
     - mergecommitblocker

config/testgrids/kubernetes/sig-cluster-lifecycle/config.yaml

@@ -13,7 +13,6 @@ dashboard_groups:
     - sig-cluster-lifecycle-cluster-api-provider-gcp
     - sig-cluster-lifecycle-cluster-api-provider-ibmcloud
     - sig-cluster-lifecycle-cluster-api-provider-openstack
-    - sig-cluster-lifecycle-cluster-api-bootstrap-provider-kubeadm
     - sig-cluster-lifecycle-cluster-api-provider-docker
     - sig-cluster-lifecycle-cluster-api-provider-nested
     - sig-cluster-lifecycle-kops
@@ -43,7 +42,6 @@ dashboards:
 - name: sig-cluster-lifecycle-cluster-api-provider-ibmcloud
 - name: sig-cluster-lifecycle-cluster-api-provider-vsphere
 - name: sig-cluster-lifecycle-cluster-api-provider-openstack
-- name: sig-cluster-lifecycle-cluster-api-bootstrap-provider-kubeadm
 - name: sig-cluster-lifecycle-cluster-api-provider-docker
 - name: sig-cluster-lifecycle-cluster-api-provider-nested
 - name: sig-cluster-lifecycle-kops