Fix 500 on failure to create a private group

What does this MR do?

Fix 500 on failure to create a private group.

Why was this MR needed?

We are getting 500 errors when trying to create a private group but the path is taken.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Fixes #34068 (closed)