Update the HackerOne process to include copying reproduction steps over

Why is this change being made?

This MR is for adding a reminder to add the final reproduction steps written by our HackerOne issue, as they usually are a lot more clear than the initial reproduction steps from the researchers.

I noticed is that we don't automatically import them, as they are in a private comment. Maybe this is implied with the current step, but it was something I missed out on, so wanted to suggest to update it in the documentation at least!

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added, and the content is SAFE
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  • The when to get approval handbook section explains the workflow in more detail
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