Add optional path parameter and fix tests

What does this MR do?

Adds missing optional path parameter to Create project for user API

Are there points in the code the reviewer needs to double check?

I think we should make the Create project API and Create project for user API consistent with regards to the name and path parameters. For "Create project" API, we can provide either one of name and path, but for "Create project for user" API, name is required and path is optional.

Why was this MR needed?

Users are unable to use Create project for user API to create a project with a custom path since the path parameter is ignored.

Does this MR meet the acceptance criteria?

• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together
• Add changelog entry
• Assign a reviewer

What are the relevant issue numbers?

Closes #33242 (closed)

/cc @MrChrisW @smcgivern @stanhu