Fix Perl module Module::Pluggable such that it can find plugins that live in
symlinked directories.

Patch borrowed/adapted from Nixpkgs.

--- Module-Pluggable-5.2/lib/Module/Pluggable/Object.pm   2015-04-08 23:28:48.120164135 -0500
+++ Module-Pluggable-5.2/lib/Module/Pluggable/Object.pm   2015-04-08 23:30:27.032166704 -0500
@@ -164,7 +164,7 @@
         my $sp = catdir($dir, (split /::/, $searchpath));

         # if it doesn't exist or it's not a dir then skip it
-        next unless ( -e $sp && -d _ ); # Use the cached stat the second time
+        next unless ( -e $sp );

         my @files = $self->find_files($sp);

@@ -279,7 +279,7 @@
                              (my $path = $File::Find::name) =~ s#^\\./##;
                              push @files, $path;
                            }
-                      }, $search_path );
+                      }, "$search_path/." );
     }
     #chdir $cwd;
     return @files;</td><td class='sub right'></td></tr></table>
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<tr><td><span title='2023-01-30 12:39:40 +0200'>2023-01-30</span></td><td><a href='/guix/commit/gnu/packages/dbm.scm?id=4cf1acc7f3033b50b0bf19e02c9f522d522d338c'>Merge remote-tracking branch 'origin/master' into core-updates</a><span class='msg-avail'>...<span class='msg-tooltip'> Conflicts:
	doc/guix.texi
	gnu/local.mk
	gnu/packages/admin.scm
	gnu/packages/base.scm
	gnu/packages/chromium.scm
	gnu/packages/compression.scm
	gnu/packages/databases.scm
	gnu/packages/diffoscope.scm
	gnu/packages/freedesktop.scm
	gnu/packages/gnome.scm
	gnu/packages/gnupg.scm
	gnu/packages/guile.scm
	gnu/packages/inkscape.scm
	gnu/packages/llvm.scm
	gnu/packages/openldap.scm
	gnu/packages/pciutils.scm
	gnu/packages/ruby.scm
	gnu/packages/samba.scm
	gnu/packages/sqlite.scm
	gnu/packages/statistics.scm
	gnu/packages/syndication.scm
	gnu/packages/tex.scm
	gnu/packages/tls.scm
	gnu/packages/version-control.scm
	gnu/packages/xml.scm
	guix/build-system/copy.scm
	guix/scripts/home.scm
</span></span></td><td>Efraim Flashner</td></tr>