[Perl/perl5] b17e77: test SvPVbyte*() and SvPVutf8*() variants setlen

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: b17e77fbd875a907749400afcdb9da990643edad
      https://github.com/Perl/perl5/commit/b17e77fbd875a907749400afcdb9da990643edad
  Author: Tony Cook <tony@develop-help.com>
  Date:   2022-11-21 (Mon, 21 Nov 2022)

  Changed paths:
    M ext/XS-APItest/APItest.xs
    M ext/XS-APItest/t/svpv.t
    M ext/XS-APItest/t/svpv_magic.t

  Log Message:
  -----------
  test SvPVbyte*() and SvPVutf8*() variants set len

These macros have limited use in core:

- only Socket uses SvPVbyte_nomg()
- nothing uses SvPVutf8_nomg()

Update the existing tests to ensure len is set properly.

Related to #20507

• [Perl/perl5] b17e77: test SvPVbyte*() and SvPVutf8*() variants setlen by Tony Cook via perl5-changes