Koha: refactor availability queries for better DB locks handling
o [DEICH-6323] {origin/DEICH-6323} DEICH-6323 koha: update ILL availability query
o DEICH-6323 koha: update deactivated availability count query
o DEICH-6323 koha: fix biblio availability query ref DEICH-5924
o DEICH-6323 koha: refactor availability queries to use less cpu and db locks
Edited by Benjamin