[gnome-desktop] Update README.md to explain why the issue tracker is closed

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 330f36008e960991ec55a343841b68fc89524bb4
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Thu Oct 29 19:20:09 2020 +0000

    Update README.md to explain why the issue tracker is closed

 README.md | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/README.md b/README.md
index 3a309b0e..0e6c8c84 100644
--- a/README.md
+++ b/README.md
@@ -33,9 +33,10 @@ How to report bugs
 ==================
 
 Bugs should be reported to the [Issues section of gnome-desktop 
repository](https://gitlab.gnome.org/GNOME/gnome-desktop/-/issues).
-
-Please read the HACKING file for information on where to send changes or
-bugfixes for this package.
+Due to very high numbers of misdirected gnome-shell bugs, the issue tracker has
+unfortunately been restricted to GNOME developers only. If you have found a bug in
+this library, feel free to contact any GNOME developer and ask for your report to be
+forwarded here.
 
 Thumbnailing sandboxing
 =======================