Dynamically update kubespray at runtime

[taylor]

The docker image may have been built with an older version of kubespray which means a later release of K8s will not be compatible with the kubespray in the image. This has caused problems as seen in the CNF Testbed ticket K8s provisioning ansible task fails - dict object' has no attribute 'v1.18' #344. Related ticket for this update cncf/cnf-testbed#345.

Task:

• code update
• push new image to dockerhub
• test on cncf.ci cidev environment
• test on dev
• test on staging
• test on production

[michaelspedersen]

Image has been pushed to Docker Hub with tag "dynamic-kubespray-update". CNF Testbed has been updated to reflect changes. Once merged to master we can update other images (and modify CNF Testbed code as needed)