utils/scancpan: warn when a module is a perl core module

we don't want create new BR package with perl core module,
because core modules are already included in perl distribution,
and built with the BR package perl.

Signed-off-by: Francois Perrad <francois.perrad@gadz.org>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

utils/scancpan

@@ -611,6 +611,9 @@ sub fetch {
     unless ($dist{$name} && !$top) {
         say qq{fetch ${name}} unless $quiet;
         my $result = $mcpan->release( distribution => $name );
+        my $main_module = $result->{main_module};
+        push @info, qq{[$name] $main_module is a core module}
+            if $top && Module::CoreList::is_core( $main_module, undef, $] );
         $dist{$name} = $result;
         $license_files{$name} = {};
         eval {