[tracker-oci-images/sam/alpine-gtk-doc] alpine: Add gtk-doc to image

[Sam Thursfield <sthursfield src gnome org>]

commit 35fea8013984770c5eeeeecb33027779c3860a47
Author: Sam Thursfield <sam afuera me uk>
Date:   Sun Mar 15 15:33:18 2020 +0100

    alpine: Add gtk-doc to image
    
    Image size increases from 554 to 561 MiB.
    
    Needed for https://gitlab.gnome.org/GNOME/tracker/-/merge_requests/204

 alpine/prepare.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/alpine/prepare.sh b/alpine/prepare.sh
index 786141c..7e3ab2f 100644
--- a/alpine/prepare.sh
+++ b/alpine/prepare.sh
@@ -2,7 +2,7 @@
 
 echo 'https://alpine.global.ssl.fastly.net/alpine/edge/community/' >> /etc/apk/repositories
 apk add -U alpine-sdk bash-completion dbus-dev git glib-dev gobject-introspection-dev \
-           icu-dev json-glib-dev libsoup-dev libxml2-dev meson networkmanager-dev \
+           gtk-doc icu-dev json-glib-dev libsoup-dev libxml2-dev meson networkmanager-dev \
            py3-gobject3 py3-setuptools sqlite-dev vala
 
 addgroup -S tracker