Pin the oc-chef-pedant chef-zero based tests to chef 12.x
Pin the oc-chef-pedant chef-zero based tests to chef 12.x

Pedant is _not_ compatible chef 13.x. There are 70 failures that will
need to be resolved before the chef-zero based tests will complete
successfully. When the oc-chef-pedant chef-zero test bundles the
`chef-zero v5.3.2` dependencies it'll pull in chef 13.x. This change
modifies `chef-zero`'s embedded chef dependency to 12.x.

Signed-off-by: Ryan Cragun <b1c1d8736f20db3fb6c1c66bb1455ed43909f0d8@ryan.ec>

chef/chef-server,juliandunn/chef-server-1,juliandunn/chef-server-1,chef/chef-server,juliandunn/chef-server-1,juliandunn/chef-server-1,chef/chef-server,chef/chef-server,chef/chef-server,juliandunn/chef-server-1,chef/chef-server