Replace broken link with a new link

Replace http://www.perlfoundation.org/perl6/index.cgi?perl_6_delta_tablet with https://docs.perl6.org/language/5to6-overview for tips on translating Perl 5 to Perl 6

doc/Language/5to6-nutshell.pod6

@@ -1774,7 +1774,7 @@ live on GitHub. An online converter may become available at some point.
 =item L<https://perlgeek.de/en/article/5-to-6>
 =item L<https://github.com/Util/Blue_Tiger/>
 =item L<https://perl6advent.wordpress.com/2011/12/23/day-23-idiomatic-perl-6/>
-=item L<http://www.perlfoundation.org/perl6/index.cgi?perl_6_delta_tablet>
+=item L<https://docs.perl6.org/language/5to6-overview>
 
 =end pod