Fix item name and namespace text overflow in Projects dropdown

What does this MR do?

Fixes text overflow for long project and namespace names.

Why was this MR needed?

Overflowing text due to length leads to broken UI on Projects dropdown, this MR fixes it.

Screenshots

Before

After

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [ ] Documentation created/updated
• [ ] API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • [ ] Has been reviewed by Backend
  • [ ] Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• [ ] Internationalization required/considered

What are the relevant issue numbers?

Closes #39827 (closed)