[gnome-system-monitor] Update bugzilla references to gitlab

[Robert Roth <robertroth src gnome org>]

commit d9ee140bbb214c6745d9b1e9c26cb9f37515b3e7
Author: Robert Roth <robert roth off gmail com>
Date:   Mon May 28 14:47:53 2018 +0300

    Update bugzilla references to gitlab

 README                              | 2 +-
 gnome-system-monitor.appdata.xml.in | 2 +-
 meson.build                         | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/README b/README
index a4195982..d7ee726e 100644
--- a/README
+++ b/README
@@ -12,5 +12,5 @@ Optional dependencies :
 BUGS
 -------------
 Please file System-Monitor bugs at:
-http://bugzilla.gnome.org/enter_bug.cgi?product=system-monitor
+https://gitlab.gnome.org/GNOME/gnome-system-monitor/issues
 
diff --git a/gnome-system-monitor.appdata.xml.in b/gnome-system-monitor.appdata.xml.in
index bc4577f4..7181f40e 100644
--- a/gnome-system-monitor.appdata.xml.in
+++ b/gnome-system-monitor.appdata.xml.in
@@ -44,7 +44,7 @@
 
   <developer_name>The GNOME Project</developer_name>
 
-  <url type="bugtracker">https://bugzilla.gnome.org/enter_bug.cgi?product=system-monitor</url>
+  <url type="bugtracker">https://gitlab.gnome.org/GNOME/gnome-system-monitor/issues</url>
 
   <!--GNOME Projects usually have no per-app donation page-->
   <url type="donation">http://www.gnome.org/friends/</url>
diff --git a/meson.build b/meson.build
index 15238524..4bdf6da7 100644
--- a/meson.build
+++ b/meson.build
@@ -1,4 +1,4 @@
-# http://bugzilla.gnome.org/enter_bug.cgi?product=system-monitor
+# https://gitlab.gnome.org/GNOME/gnome-system-monitor/issues
 project('gnome-system-monitor',
   'c', 'cpp',
   default_options : [