[Perl/perl5] 12c687: Support %#p format (#18709)

[Dominic Hamon via perl5-changes]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: 12c68733611a690880d3f4621d10c9110b8ac7e4
      
https://github.com/Perl/perl5/commit/12c68733611a690880d3f4621d10c9110b8ac7e4
  Author: Dominic Hamon <dominicha...@users.noreply.github.com>
  Date:   2021-04-10 (Sat, 10 Apr 2021)

  Changed paths:
    M AUTHORS
    M sv.c
    M t/op/sprintf.t

  Log Message:
  -----------
  Support %#p format (#18709)

* Support %#p form of %..p

Fix #18289

* Better testing

* Add myself to AUTHORS

* Add a comment