Enable cmpVERSION.pl checking of upstream cpan as well as upstream blead

There is no reason why upstream cpan modules should not also have their
$VERSIONs bumped if they differ from the previous release. Even if they
are temporarily locally patched for blead, that temporary patch should
include a $VERSION bump.

Author: steve-m-hay

t/porting/cmp_version.t

@@ -20,4 +20,4 @@ require 't/test.pl';
 my $source = find_git_or_skip('all');
 chdir $source or die "Can't chdir to $source: $!";
 
-system "$^X Porting/cmpVERSION.pl --exclude --tap";
+system "$^X Porting/cmpVERSION.pl --tap";