Improve readability of numbered list

Why is this change being made?

The second numbered list in the image below looks orphaned. Content wise, it's a continuation of the first number list with the lead in sentence "Below are a few things to remember when creating issues:".

However, Pro Tip: splits the list and causes the numbering to restart.

This change updates the second list so that the numbering continues and is logically part of the first list.

Author Checklist

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• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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