Bug 22799: Avoiding batch item modification case sensitivity when entering barcodes

Bug 22799: Avoiding batch item modification case sensitivity when entering barcodes

Note: this fixes the bug that is present right now where batch item
modification barcode matching is case sensitive, but if Koha barcodes
ever do become case sensitive, this patch will need to be removed.

To test:
1) Make/use an item with a barcode with letters in it. For testing
purposes, I'll be using an item with the barcode 'abcde'.
2) Go to Tools -> Batch item modification and enter this barcode in the
barcode list text input field, but change the case of one or some
letters. (i.e. enter the barcode in the field as 'abCDE')
3) Click Continue
4) Notice that the next page shows an error 'the following barcodes were
not found', but the item still shows underneath (was correctly fetched from database).
5) Create a text file and put the changed-case barcode in it (i.e. put
the barcode 'abCDE' in the text file)
6) Go back to batch item modification and upload the
text file as a barcode file
7) Notice same error as in Step 4
8) Apply patch and refresh page
9) Run through steps 1 to 6. There should no longer be an error and the
barcodes should be found as expected.

Sponsored-by: South Taranaki District Council
Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Signed-off-by: Kyle Hall <kyle@bywatersolutions.com>
Signed-off-by: Donna Bachowski <donna@bywatersolutions.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 2071fa4aca27f6748f32fd62037a203df2347141)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>