Bug 24616: Do not save form if user press cancel

Bug 24616: Do not save form if user press cancel

If one starts to copy a notice but then cancels
this when pop-up is displayed, changes are still
saved. This patch fixes this.

To test:
1. Copy notice to a library where it already exists
2. Press save and then cancel when pop-up is
displayed
=> Form and changes are still saved
3. Apply this patch.
4. Repeat steps 1. and 2.
=> Form is no longer saved

Sponsored-by: Koha-Suomi Oy
Signed-off-by: ml-inlibro <marie-luce.laflamme@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>