improve the check by checking for methods that exclude
using string_view, rather than checking for methods that
__can__ use string_view, which leads to exposing
some holes in our o3tl/string_view.hxx coverage.
Change-Id: Ic9dd60441c671f502692f9cd2a1bb67301c4b960
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/150277
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
