[ci] Remove unnecessary container build tasks

Since Train release, we use upstream hyperkube image for fedora-atomic
(when use_podman=True label is set) and fedora-coreos drivers. The last
image we needed to build through the CI was for v1.15.x (because the
Kubernetes project maintains release branches for the most recent three
minor releases: 1.18, 1.17, 1.16 [0]) and v1.16.x+ has never been
supported by the fedora-atomic driver without the use_podman label.

This PS proposes removing the Ansible tasks to build these containers
through the CI. This does not affect already published older images:
https://hub.docker.com/search?q=openstackmagnum%2Fkubernetes&type=image.

[0] https://kubernetes.io/docs/setup/release/version-skew-policy/#supported-versions

Story: 2005124
Task: 39398

Change-Id: I458767dc12b46d665777ebe019c46565f37dd959

playbooks/container-builder-vars.yaml

@@ -1,18 +1,6 @@
 magnum_src_dir: "src/opendev.org/openstack/magnum"
 
 magnum_repository: openstackmagnum
-kubernetes_version_v1_11: v1.11.10
-kubernetes_version_v1_12: v1.12.10
-kubernetes_version_v1_13: v1.13.12
-kubernetes_version_v1_14: v1.14.10
-kubernetes_version_v1_15: v1.15.11
-kubernetes_version_v1_16: v1.16.2
-kubernetes_images:
-  - name: kubernetes-apiserver
-  - name: kubernetes-controller-manager
-  - name: kubernetes-kubelet
-  - name: kubernetes-scheduler
-  - name: kubernetes-proxy
 
 magnum_images:
   - name: heat-container-agent

playbooks/container-builder.yaml

@@ -13,88 +13,6 @@
           with_items: "{{ magnum_images }}"
           retries: 10
 
-    - name: "Build kubernetes images v1.11"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_11}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_11}}"
-              ADD_KUBE_ALLOW_PRIV: "true"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
-    - name: "Build kubernetes images v1.12"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_12}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_12}}"
-              ADD_KUBE_ALLOW_PRIV: "true"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
-    - name: "Build kubernetes images v1.13"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_13}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_13}}"
-              ADD_KUBE_ALLOW_PRIV: "true"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
-    - name: "Build kubernetes images v1.14"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_14}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_14}}"
-              ADD_KUBE_ALLOW_PRIV: "true"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
-    - name: "Build kubernetes images v1.15"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_15}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_15}}"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
-    - name: "Build kubernetes images v1.16"
-      block:
-        - name: "Build {{ magnum_repository }}/{{ item.name }}:{{ item.tag }} image"
-          docker_image:
-            path: "{{ magnum_src_dir }}/dockerfiles/{{ item.name }}"
-            name: "{{ magnum_repository }}/{{ item.name }}"
-            tag: "{{kubernetes_version_v1_16}}"
-            buildargs:
-              KUBE_VERSION: "{{kubernetes_version_v1_16}}"
-            push: no
-          with_items: "{{ kubernetes_images }}"
-          retries: 10
-
     - name: "Build helm-client image"
       block:
         - docker_image: