Make sure kitchen test dependencies formulas are always fetched from correct branch

Change-Id: I8c7171eed287a07e06c4fe98f6357896aadf2cc7
Related: PROD-29251
diff --git a/.kitchen.yml b/.kitchen.yml
index da4f929..83094e9 100644
--- a/.kitchen.yml
+++ b/.kitchen.yml
@@ -42,9 +42,11 @@
     - name: postgresql
       repo: git
       source: https://gerrit.mcp.mirantis.com/salt-formulas/postgresql
+      branch: <%=ENV['GERRIT_BRANCH'] || 'master' %>
     - name: rsyslog
       repo: git
       source: https://gerrit.mcp.mirantis.com/salt-formulas/rsyslog
+      branch: <%=ENV['GERRIT_BRANCH'] || 'master' %>
 
 docker_images:
   - &xenial-20177 <%=ENV['IMAGE_XENIAL_20177'] || 'docker-dev-local.docker.mirantis.net/epcim/salt/saltstack-ubuntu-xenial-salt-2017.7/salt:2018_11_19'%>