Add missing python2 makedepends (close FS#34900)

PKGBUILD

@@ -8,7 +8,7 @@ arch=(i686 x86_64)
 url="http://live.gnome.org/dconf"
 license=('LGPL2.1')
 depends=('glib2' 'gtk-update-icon-cache')
-makedepends=('vala' 'gtk3' 'intltool' 'docbook-xsl' 'python')
+makedepends=('vala' 'gtk3' 'intltool' 'docbook-xsl' 'python' 'python2')
 optdepends=('gtk3: for dconf-editor')
 install=dconf.install
 source=(http://download.gnome.org/sources/$pkgname/${pkgver%.*}/$pkgname-$pkgver.tar.xz)