[pitivi] help: Link to Gitlab instead of fdo Phabricator

[Andre Klapper <aklapper src gnome org>]

commit 461d1ad72ad23c212c7e676f12f5cfa7a9d0b04c
Author: Andre Klapper <a9016009 gmx de>
Date:   Sat Sep 22 10:15:05 2018 +0200

    help: Link to Gitlab instead of fdo Phabricator

 help/C/sysreq.page | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/help/C/sysreq.page b/help/C/sysreq.page
index 4c6e27ea..35acd81f 100644
--- a/help/C/sysreq.page
+++ b/help/C/sysreq.page
@@ -41,7 +41,7 @@
   </list>
   <p>It is possible, however, to use low-quality versions of your footage during editing and use the 
high-quality versions when rendering the final output, thus allowing to bypass hardware limitations to some 
extent. This is called <em>proxy editing</em>. This feature, however, is not yet available in 
<app>Pitivi</app>.</p>
   <note style="bug">
-    <p>You can track the state of proxy editing in <app>Pitivi</app> through <link 
href="https://phabricator.freedesktop.org/T2455";>task T2455</link>.</p>
+    <p>You can track the state of proxy editing in <app>Pitivi</app> through <link 
href="https://gitlab.gnome.org/GNOME/pitivi/issues/743";>task 743</link>.</p>
   </note>
   <p>Software requirements are covered in <link xref="gstreamer">Gstreamer and compatibility</link> and 
<link xref="effects">Introduction to effects</link>.</p>
 </page>