Adding new directory for the new 'Research Insights' page

Why is this change being made?

As part of the Research OKR, one of the KRs involves documenting the Actionable Insight process. Since this process is net-new to the existing documentation in the handbook, a new handbook page needs to be created. Using the same page structure of 'a directory for every page' that the existing UX Research documentation follows, this MR accounts for creating the directory to house the new upcoming page.

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per [say-why-not-just-what][transparency]
• Assign this change to the correct DRI
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to your manager.
  • If your manager does not have merge rights, please ask someone to merge it AFTER it has been approved by your manager in [#mr-buddies][mr-buddies-slack].
  • If the changes relate to any part of the project other than updates to content and/or data files please make sure to ping @gl-static-site-editor in a comment for a review and merge. For example changes to .gitlab-ci.yml, JavaScript/CSS/Ruby code or the layout files.