Hide button "New schedule" on schedule pipeline page if user is not allowed to schedule

What does this MR do?

Hide "New schedule" button on pipeline schedule page when a user is not allowed to schedule one.

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

Maybe the tests that I have added.

Why was this MR needed?

To avoid the unauthorized user to click on "New schedule" button and have a 4xx error page.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

What are the relevant issue numbers?

Closes #33235 (moved)

Edited by username-removed-378947