[sysprof/wip/nielsdg/update-readme-for-mailing-list] README: Add links to GitLab and Discourse

[Niels De Graef <nielsdg src gnome org>]

commit 7dc7f5d405f45f268d5b9a56679b8cf3ced5205e
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Sun Jun 14 09:44:17 2020 +0200

    README: Add links to GitLab and Discourse

 README.md | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/README.md b/README.md
index 6e304cc..16e02dc 100644
--- a/README.md
+++ b/README.md
@@ -4,10 +4,13 @@ stacktraces which are then interpreted by the userspace program
 
 See the [Sysprof homepage](http://sysprof.com/) for more information.
 
-Questions, patches and bug reports should be sent to the sysprof
-mailing list [sysprof-list gnome org](mailto:sysprof-list gnome org).
+Merge requests and bug reports should be sent to sysprof's [repository on
+GNOME's GitLab instance](https://gitlab.gnome.org/GNOME/sysprof). For general
+discussion and questions, you can create a new topic in [GNOME's
+Discourse](https://discourse.gnome.org).
 
-The list is archived in <https://mail.gnome.org/archives/sysprof-list/>.
+The former mailing list is archived in
+<https://mail.gnome.org/archives/sysprof-list/>.
 
 Debugging symbols
 -----------------