Bug 27191: Set focus on first input when adding a new patron category

Bug 27191: Set focus on first input when adding a new patron category

When adding a new patron category, the focus/cursor should be
in the first input field of the form: Category code

To test:
* Add a new patron category in administration > patron categories
  - cursur is in no field
* Apply patch
* Add another new patron category
  - cursor is now in the first input field of the form: Category code

Signed-off-by: Barbara Johnson <barbara.johnson@bedfordtx.gov>
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>