Sponsors Agreements can't be created for non-published Sponsors

[Crixu]

Describe the bug

We've tried to generate the sponsor agreements for WordCamp Europe next year but the dropdown list on /admin.php?page=wcdocs is empty. We figured out that sponsors will only appear once they're status is set to published.
To be published they need to pay and sign the agreement.

Proposal:
Allow the creation of sponsor agreements independent of the sponsor status or at least allow "Pending" as a valid option to generate a doc.

To reproduce

Steps to reproduce the behavior:

1. Go to WP Admin
2. Go to "Docs"
3. Select Sponsorship Agreement
4. Find no sponsors if none is published

Expected behavior

Have the option to select from any sponsor CPT that is created on the network site.
A clear and concise description of what you expected to happen.

Screenshots / Screencasts

WordCamp

If this is a problem on a specific WordCamp's site, list the site or page URL here.

System (please complete the following information)

• Device: Laptop
• OS: MacOS
• Browser Arc

Security Issues

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