Add docker base image now Ubuntu 22.04

What does this MR do?

Add notification of Docker base image changing to Ubuntu 22.04

Upgrading to Ubuntu 22.04, also updated Openssh Server to openssh-server/now 1:8.9p1-3ubuntu0.1 amd64 which includes the deprecation of ssh-keyscan -t rsa <hostname> which can be used to provide dynamic ssh auth in CI/CD pipelines.

Information on the deprecation can be found at https://www.openssh.com/txt/release-8.7

Related issues

Make GitLab Docker image use Ubuntu 22.04 as a base

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