Bug description:

ISSN search is case sensitive (ex. : 0015-220x or 0015-220X don't return the same result).
Remarks : it works fine with the ISBN (ex. : 270565769x or 270565769X return the same result).

Expected behavior:

The case shoudn't matter (0015-220x and 0015-220X should return the same results).

Steps to Reproduce:

1. Search for 0015-220X
2. See there is no result
3. Search for 0015-220x
4. See there is one record (https://ils.test.rero.ch/global/documents/1146)

Context

Server:

• production: bib.rero.ch and ils.bib.uclouvain.be
• test: bib.test.rero.ch
• dev: ilsdev.test.rero.ch
• dev test : ils.test.rero.ch

Version:

v1.9.0