[library-web] add an explicit reference to devhelp

[Frederic Peters <fpeters src gnome org>]

commit 309ff509e3beb70f718e2e4927378ea58ef58b29
Author: Frédéric Péters <fpeters 0d be>
Date:   Sun Apr 15 18:29:59 2018 +0200

    add an explicit reference to devhelp

 data/extra-tarballs |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/data/extra-tarballs b/data/extra-tarballs
index 6ddc19b..0d62490 100644
--- a/data/extra-tarballs
+++ b/data/extra-tarballs
@@ -80,6 +80,9 @@ gnome://libgsf
 gnome://easytag?min=2.2
 gnome://NetworkManager?min=1.0
 
+# applications, no longer managed by the release team
+gnome://devhelp?min=3.28
+
 # GUPnP - see https://bugzilla.gnome.org/show_bug.cgi?id=648119
 gnome://gssdp?min=0.10
 gnome://gupnp?min=0.16