Fix minor grammar mistakes

(cherry picked from commit 8c040fe97e602b6b0747f94db9f16ad1c1e12e54)

index.rst

@@ -30,7 +30,7 @@ in the top left corner.
           <https://github.com/godotengine/godot-docs/issues>`_,
           help us `translate the documentation
           <https://hosted.weblate.org/engage/godot-engine/>`_ into your
-          language, or discuss with us on either the ``#documentation``
+          language, or talk to us on either the ``#documentation``
           channel on `Discord <https://discord.gg/zH7NUgz>`_, or the
           ``#godotengine-doc`` channel on `irc.freenode.net
           <http://webchat.freenode.net/?channels=#godotengine-doc>`_!