Fix V< > showing up in heading for regex

Author: samcv

doc/Language/regexes.pod6

@@ -435,7 +435,7 @@ say so 'abababa' ~~ /a .* aba/;   # True
 say so 'abababa' ~~ /a .*: aba/;  # False
 =end code
 
-=head1 X<Alternation: C<V«||»>|regex,||>
+=head1 X<Alternation: C<||>|regex,||>
 
 To match one of several possible alternatives, separate them by C<||>; the
 first matching alternative wins.
@@ -456,7 +456,7 @@ non-whitespace characters, followed by zero or more spaces, followed by the
 equals sign C<=>, followed again by optional whitespace, followed by another
 string of non-whitespace characters.
 
-=head1 X<Longest Alternation|regex,|>
+=head1 X<Longest Alternation: C<|>|regex,|>
 
 In regexes branches separated by C<|>, the longest match wins, independent of
 the lexical ordering in the regexes.