fix t/9050-pod.t: skip G11 Pod::Checker errors check when Pod::Checker < 1.51 to avoid false FAILs caused by mis-reported errors for valid L</section>, L</"section">, and L<URL> syntax on older Perl installations (CPAN Testers FAIL fix)
fix lib/mb.pm: update =head1 Perl 5.42 and source::encoding POD to accurately describe that no source::encoding; is appended on the same line as qualifying use VERSION statements (not in a BEGIN block), and clarify that only DAMEMOJI inside string and regexp literals are escaped; comments and POD are left untouched