docs: update contibutor docs

[prasadkatti]

Description

• fix the slack channel link
• add docs on how to generate docs locally

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[k8s-ci-robot]

Hi @prasadkatti. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 54.09%. Comparing base (5634fa2) to head (8ce86a1).
⚠️ Report is 654 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@ ## main #2961 +/- ## ======================================= Coverage 54.09% 54.09% ======================================= Files 144 144 Lines 8291 8291 ======================================= Hits 4485 4485 Misses 3479 3479 Partials 327 327 

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[johngmyers]

/ok-to-test

[johngmyers]

/retest

[johngmyers]

Thanks!
/lgtm
/assign @kishorj

kOps uses netlify for previewing docs; perhaps we could get that set up for this project as well.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kishorj, prasadkatti

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• OWNERS [kishorj]

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