release: version bump for package cloud script

packaging/publish/publish_testing.sh

@@ -1,6 +1,6 @@
 #! /usr/bin/env bash
-deb_ver=4.2.0-beta1
-rpm_ver=4.2.0-beta1
+deb_ver=4.3.0-beta1
+rpm_ver=4.3.0-beta1
 
 wget https://s3-us-west-2.amazonaws.com/grafana-releases/release/grafana_${deb_ver}_amd64.deb