Bug 36130: Fetch all batches for the table

Test plan, ktd:
- Add 'FreeForm' backend and enable ILLModule, run:
bash <(curl -s https://raw.githubusercontent.com/ammopt/koha-ill-dev/master/start-ill-dev.sh)
- Install a metadata enrichment plugin, e.g.:
https://github.com/PTFS-Europe/koha-plugin-api-pubmed/releases
- Add 21 batches, run the following command in kshell:
for x in {1..21}; do echo "INSERT INTO illbatches (name, backend, library_id, status_code, patron_id) VALUES ('$x', 'FreeForm', 'CPL', 'NEW', 52);"; done | koha-mysql kohadev
- Visit ILL batches page:
<INTRA_URL>/cgi-bin/koha/ill/ill-requests.pl?method=batch_list
- Notice only 20 batches show.
- Apply patch. Notice 20 batches show but now there is a page 2 link.
- Test page 2 works as expected, delete a batch, notice only 1 page with 20 batches shows again.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Edith Speller <edith.speller@ukhsa.gov.uk>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>

koha-tmpl/intranet-tmpl/prog/js/ill-batch-table.js

@@ -27,7 +27,7 @@
         table = initTable();
 
         // Do the initial data population
-        window.doBatchApiRequest('', {
+        window.doBatchApiRequest( '?_per_page=-1', {
                 headers: {
                     'x-koha-embed': '+strings,requests+count,patron'
                 }