Clarify the empty-state message for the projects "pending deletion" tab

Problem to solve

On the Projects "pending deletion" tab, when there are no projects pending deletion, the empty-state message says: "You haven’t removed any projects." That is a bit misleading, because all projects pending deletion will appear on this page regardless of who removed them. Also, we plan to allow owners to list projects pending deletion on the same page, and need this message to be more generic for them as well.

Proposal

1. Update the tab

- Deleted projects
+ Pending deletion

2. Update the empty state message

- You haven’t removed any projects. 
+ No projects pending deletion found
- Projects which are removed and are yet to be permanently removed are visible here.
+ Projects that are pending deletion that you have access to are listed here. Learn more.

3. Add Learn more link to docs

4. Center align empty state message body text

5. Update the documentation to reflect these changes

Before

After

What does success look like?

Any user that visits this page should be able to interpret why no projects are being displayed