chore: add support for k8s v1.17.9 on Azure Stack

[JesusAlvarezTorres]

Reason for Change:

Pre-pull Azure Stack's custom images for K8s v1.17.9

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

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[jackfrancis]

lgtm after rebase

[JesusAlvarezTorres]

@jackfrancis , just pushed the rebase

[jackfrancis]

/lgtm

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[APPROVALNOTIFIER] This PR is APPROVED

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

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