Fix leave action label for project members

What does this MR do and why?

Related to #387377 (closed)
Finishing up community contribution that contributor was not able to finish - !139996 (closed)

Fixes bug where leave action says Leave group for a project member.

MR acceptance checklist

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Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Create a project
2. Go to that project -> Manage -> Members
3. Click the More actions dropdown, the leave action should say Leave project