Add links to describe repeat step changes in more details

[porunov]

Fixes #3799

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Thank you for contributing to JanusGraph!

In order to streamline the review of the contribution we ask you
to ensure the following steps have been taken:

For all changes:

• Is there an issue associated with this PR? Is it referenced in the commit message?
• Does your PR body contain #xyz where xyz is the issue number you are trying to resolve?
• Has your PR been rebased against the latest commit within the target branch (typically master)?
• Is your initial contribution a single, squashed commit?

For code changes:

• Have you written and/or updated unit tests to verify your changes?
• If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under ASF 2.0?
• If applicable, have you updated the LICENSE.txt file, including the main LICENSE.txt file in the root of this repository?
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For documentation related changes:

• Have you ensured that format looks appropriate for the output in which it is rendered?

[li-boxuan]

Do you think it's possible to create a JanusGraph official medium account, and copy your article there? And of course, you can link to the original post in the JanusGraph post. The idea is the links on official doc should be as permanent as possible.

[porunov]

Makes sense. Will do that