feat: add support for Kubernetes v1.16.12

[mboersma]

Reason for Change:
See https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.16.md#changelog-since-v11611

Issue Fixed:

Requirements:

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

Notes:

[mboersma]

/hold

This has a temporary commit for testing that should be discarded before merging.

[codecov]

Codecov Report

Merging #3551 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3551   +/-   ##
=======================================
  Coverage   73.19%   73.19%           
=======================================
  Files         147      147           
  Lines       25078    25078           
=======================================
  Hits        18355    18355           
  Misses       5589     5589           
  Partials     1134     1134           

Impacted Files	Coverage Δ
pkg/api/common/versions.go	96.84% <ø> (ø)

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[mboersma]

This passed CI, so I'll strip off the testing commit and it should be ready for review.

[mboersma]

/hold cancel

[chewong]

With #3532, kube-proxy image is used for kube-proxy container instead of hyperkube. Could you add 1.16.12 in https://github.com/Azure/aks-engine/blob/master/vhd/packer/install-dependencies.sh#L384-L392?

[mboersma]

Could you add [kube-proxy] 1.16.12...

Good catch! Added.

[chewong]

/hold
I think there are plans to drop 1.16.11 support after v0.53.0 is released and resume using hyperkube for kube-proxy image.

[jackfrancis]

@chewong @mboersma we don't need to worry about dropping v1.16.11 with this change, we can continue to include 1.16 kube-proxy artifacts in the VHD spec as @chewong pointed out earlier in this PR thread. We're good on that path!

[jackfrancis]

/hold release

[jackfrancis]

/lgtm

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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[acs-bot]

New changes are detected. LGTM label has been removed.

[mboersma]

/hold cancel