Option to skip CI for trivial PRs

[mboersma]

Is this a request for help?:

No

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Is this an ISSUE or FEATURE REQUEST? (choose one):

FEATURE REQUEST

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What version of aks-engine?:

N/A

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Details:

Our default CI tests that run against PRs are fairly comprehensive and arguably expensive. Some PRs such as #510 are documentation-only and ideally would not trigger E2E tests.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.