Add docker for desktop and minikube instructions

[pwplusnick]

Changes

This change will add instructions for creating a local development environment using both
minikube and Kubernetes on Docker for Desktop. This change will make it easier for those
without a cloud account to contribute tekton pipeline.

Submitter Checklist

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• Includes tests (if functionality changed/added)
• Includes docs (if user facing)
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• If you are adding a new binary/image to the cmd dir, please update
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If API changes
are included, additive changes
must be approved by at least two OWNERS
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must be approved by more than 50% of the OWNERS,
and they must first be added
in a backwards compatible way.

Release Notes

Describe any user facing changes here, or delete this block.

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- API changes
- Bug fixes
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[tekton-robot]

Hi @pwplusnick. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[EliZucker]

/ok-to-test /lgtm

[ghost]

/lgtm

[vdemeester]

/lgtm

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: pwplusnick, vdemeester

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