Bug 5327: Patch removes unneeded self=shift from TTParser::unshift_token

Removed  unneeded self=shift from unshift_token
(as peek and next do not take a self, makes interface more consistent)

http://bugs.koha-community.org/show_bug.cgi?id=5327
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>

C4/TTParser.pm

@@ -22,7 +22,6 @@ sub next_token{
 
 #unshift token back on @tokens
 sub unshift_token{
-    my $self = shift;
     unshift @tokens, shift;
 }