git-remote-mediawiki: change style in a regexp

Change '[\n]' to '\n': brackets are useless here.

Signed-off-by: Célestin Matte <celestin.matte@ensimag.fr>
Signed-off-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/mw-to-git/git-remote-mediawiki.perl

@@ -1271,7 +1271,7 @@ sub get_mw_namespace_id {
 		# Look at configuration file, if the record for that namespace is
 		# already cached. Namespaces are stored in form:
 		# "Name_of_namespace:Id_namespace", ex.: "File:6".
-		my @temp = split(/[\n]/, run_git("config --get-all remote."
+		my @temp = split(/\n/, run_git("config --get-all remote."
 						. $remotename .".namespaceCache"));
 		chomp(@temp);
 		foreach my $ns (@temp) {