ref-manual/resources.rst: improve description of mailing lists

- Mention docs@lists.yoctoproject.org
- Refer to the specific web page about all mailing lists,
  instead of just the website home page.

(From yocto-docs rev: b415769d73dde835ec204d70ae35be2a58251961)

Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Reviewed-by: Quentin Schulz <foss+yocto@0leil.net>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/resources.rst

@@ -82,8 +82,10 @@ instructions:
 -  :yocto_lists:`/g/yocto-announce` --- mailing list to
    receive official Yocto Project release and milestone announcements.
 
-For more Yocto Project-related mailing lists, see the
-:yocto_home:`Yocto Project Website <>`.
+-  :yocto_lists:`/g/docs` --- discussion mailing list about the Yocto Project
+   documentation.
+
+See also :yocto_home:`the description of all mailing lists </community/mailing-lists/>`.
 
 .. _resources-irc: