update for Debian buster

* update for Debian buster
* update to debhelper 12

debian/changelog

@@ -1,6 +1,8 @@
 cacert-boardvoting (0.6.0-2) UNRELEASED; urgency=medium
 
   * Add missing license reference
+  * update for Debian buster
+  * update to debhelper 12
 
  -- Jan Dittberner <jandd@cacert.org>  Mon, 12 Aug 2019 19:57:13 +0200
 

debian/compat

@@ -1 +0,0 @@
-10

debian/control

@@ -3,7 +3,8 @@ Section: misc
 Priority: optional
 Maintainer: Jan Dittberner <jandd@cacert.org>
 Build-Depends: ca-certificates,
-               debhelper (>= 10),
+               debhelper (>= 12),
+               debhelper-compat (=12),
                git,
                golang-go (>= 2:1.11~1~),
                libsqlite3-0