Clang-Tidy: don't use cppcoreguidelines-slicing.
Clang-Tidy: don't use cppcoreguidelines-slicing.

Indeed, we are “OK” with padding issues not being reported (see
discussion at https://github.com/cellml/libcellml/pull/282).

nickerso/libcellml,cellml/libcellml,nickerso/libcellml,nickerso/libcellml,MichaelClerx/libcellml,hsorby/libcellml,cellml/libcellml,hsorby/libcellml,hsorby/libcellml,hsorby/libcellml,MichaelClerx/libcellml,cellml/libcellml,cellml/libcellml,nickerso/libcellml,MichaelClerx/libcellml