ci(kitchen): use `develop` image until `master` is ready (`amazonlinux`) [skip ci]

* Automated using https://github.com/myii/ssf-formula/pull/93

kitchen.yml

     # => SCP did not finish successfully (255):  (Net::SCP::Error)
     transport:
       max_ssh_sessions: 1
+  # Use the `develop` image temporarily until the `master` image is available
+  # Not changing the name to minimise disruption across all of the formulas
   - name: amazonlinux-2-master-py2
     driver:
-      image: netmanagers/salt-master-py2:amazonlinux-2
+      image: netmanagers/salt-develop-py2:amazonlinux-2
       provision_command:
         - curl -o bootstrap-salt.sh -L https://bootstrap.saltstack.com
-        - sh bootstrap-salt.sh -XdPbfrq -x python2 git master
+        - sh bootstrap-salt.sh -XdPbfrq -x python2 git develop
   - name: arch-base-latest-master-py2
     driver:
       image: netmanagers/salt-master-py2:arch-base-latest