Create dockershim banner

Author: chrisnegus

data/announcements/scheduled.yaml

@@ -30,6 +30,15 @@
 # leave the "announcements" key in place
 announcements:
 
+- name: Dockershim removal coming in Kubernetes 1.24
+  startTime: 2022-04-13T00:00:00 # Added in PR: 
+  endTime: 2022-05-13T00:00:00 # Expires 2022-05-19
+  style: "background: #3d4cb7"
+  title: "Dockershim removal: Read the FAQ"
+  message: |
+    As of Kubernetes 1.24, Dockershim will no longer be included in Kubernetes.
+    Read the [Dockershim Removal FAQ](https://kubernetes.io/blog/2022/02/17/dockershim-faq/) to see what this means to you.
+
 - name: Kubecon 2020 NA
   startTime: 2020-10-26T00:00:00 # Added in https://github.com/kubernetes/website/pull/24714
   endTime: 2020-11-23T00:00:00 # Removed in https://github.com/kubernetes/website/pull/25173