feat: add support for Kubernetes 1.20.2

[mboersma]

Reason for Change:

See See https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md#changelog-since-v1201

Issue Fixed:

Credit Where Due:

Does this change contain code from or inspired by another project?

• No
• Yes

Requirements:

• Kubernetes artifacts built and pushed by Azure Pipelines
• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

[codecov]

Codecov Report

Merging #4192 (7bf6b28) into master (5d932f1) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4192   +/-   ##
=======================================
  Coverage   73.42%   73.42%           
=======================================
  Files         135      135           
  Lines       20849    20849           
=======================================
  Hits        15308    15308           
  Misses       4566     4566           
  Partials      975      975           

Impacted Files	Coverage Δ
pkg/api/common/versions.go	96.37% <ø> (ø)

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[jackfrancis]

Try rebasing this on top of master now that kms is no longer a part of PR E2E (to address cloud-init data limits)

[jackfrancis]

/lgtm

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis, mboersma

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