Bug 22887: Remove superfluous warn statements

We print them in the description later

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

installer/data/mysql/updatedatabase.pl

@@ -21588,9 +21588,6 @@ if( CheckVersion( $DBversion ) ) {
                       $_->{authorised_value}, $_->{c}
                 } @$duplicates
             );
-            for my $error (@description) {
-                warn $error . "\n";
-            }
         } else {
             $dbh->do( q{ALTER TABLE `authorised_values` ADD CONSTRAINT `av_uniq` UNIQUE (category, authorised_value)} );
         }