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

Change-Id: I2a07bf8a22a109ddbfea928748d4572753e2a4b8
Related: PROD-29251
diff --git a/.kitchen.yml b/.kitchen.yml
index 5789f7c..8cf4245 100644
--- a/.kitchen.yml
+++ b/.kitchen.yml
@@ -50,9 +50,11 @@
     - name: git
       repo: git
       source: https://gerrit.mcp.mirantis.com/salt-formulas/git
+      branch: <%=ENV['GERRIT_BRANCH'] || 'master' %>
     - name: reclass
       repo: git
       source: https://gerrit.mcp.mirantis.com/salt-formulas/reclass
+      branch: <%=ENV['GERRIT_BRANCH'] || 'master' %>
 
 verifier:
   name: inspec