Bug 33655: z39.50 search no longer shows search in progress

Bug 33655: z39.50 search no longer shows search in progress

This patch adds an id to z39.50 search interface submit buttons so that
the JavaScript event for changing the cursor can be linked to that
instead of the obsolete class.

The patch also adds code copied from Bug 33233 in order to make the
"waiting" cursor revert to the default if the user uses the back button
to return to the search form.

To test, apply the patch and go to Cataloging -> New from Z39.50

- Fill in a search term and click the submit button
- Your cursor should change to a "waiting" cursor while the search is
  performed, before you're redirected to the results.
- From the results page, clicking the back button (or right-clicking the
  page and choosing "Back") should return you to the search form and
  your cursor should be a standard pointer.

Perform the same test from:

- Acquisitions -> Vendor -> Basket -> Add to basket -> From an external
  source
- Authorities -> New from Z39.50/SRU

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