doc: use https links to Wikipedia to avoid http redirects

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Reviewed-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 7cf68f0..d8209c7 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -8085,7 +8085,7 @@
 <p><strong>Pattern</strong> is by default a normal string that is matched precisely (but without
 regard to case, except in the case of pickaxe). However, when you check the <em>re</em> checkbox,
 the pattern entered is recognized as the POSIX extended
-<a href="http://en.wikipedia.org/wiki/Regular_expression">regular expression</a> (also case
+<a href="https://en.wikipedia.org/wiki/Regular_expression">regular expression</a> (also case
 insensitive).</p>
 <dl>
 <dt><b>commit</b></dt>