Document limitations and process for `collaborator` role

Why is this change being made?

This MR documents the process for getting set up as a collaborator and the limitations of the collaborator role

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
• Assign this change to the correct DRI
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assigned to @slee24

Waiting to hear about possible work around from Alex at EdCast (changing author on the pathway to the collaborator) before merging.

added 1 commit

• 518a907c - Add workaround for collaborators

Compare with previous version

@Josh_Zimmerman for your review and merge, thanks!

FYI @ralfaro @gerardo @cynthia

assigned to @Josh_Zimmerman and unassigned @slee24

marked the checklist item Assign this change to the correct DRI as completed

marked this merge request as ready

added this merge request to the merge train at position 2

merged

mentioned in commit 88500936