adding two A11y issue level: Error and warning level, and
categorizing our accesibility issues based on how the
PAC 2024 tools and WCAG behave with the different warnings/errors.
Change-Id: If4e4800497340318bb990326c64de655f24a47e8
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/177389
Tested-by: Gabor Kelemen <gabor.kelemen.extern@allotropia.de>
Tested-by: Jenkins
Reviewed-by: Balazs Varga <balazs.varga.extern@allotropia.de>
