Bug 33553: Remove unecessary GetCategories calls in templates

Bug 33553: Remove unecessary GetCategories calls in templates

This patch removes unnecessary references to
AuthorisedValues.GetCategories:

SET AuthorisedValuesCategories = AuthorisedValues.GetCategories

The AuthorisedValuesCategories variable is not used.

To test, apply the patch and go to Tools -> Patron clubs.

- If necessary, create a club template with "Allow public enrollment"
  enabled.
- Create a new club. The club creation process should work correctly.
- Open a patron account for checkout and confirm that you can enroll the
  patron in the new club via the "Clubs" tab.
- Log in to the OPAC and confirm that you can successfully enroll
  yourself in the new club via the "Clubs" tab on your patron summary
  page.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>