Bug 29867: Reindent authorized values administration template

Bug 29867: Reindent authorized values administration template

This patch performs general template cleanup to authorized values
administration: Make indentation consistent, replace tabs with spaces,
and trim trailing whitespace.

To test, apply the patch and go to Administration -> Authorized values.
Test that all functionality works correctly:

 - Adding or deleting categories
 - Adding, editing, and deleting authorized values.

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>