Chef version to 12.4.3 because they removed dependency on ohai master.

config/projects/gitlab.rb

@@ -48,7 +48,7 @@ build_iteration Gitlab::BuildIteration.new.build_iteration
 override :ruby, version: '2.1.6'
 override :ohai, version: '51a4fd97d0f03a75ae219190b29128c79b6e6a58' # Pin to 8.5.1, see https://gitlab.com/gitlab-org/omnibus-gitlab/issues/833
 override :rubygems, version: '2.2.5', source: { md5: "7701b5bc348d8da41a511ac012a092a8" }
-override :chef, version: '12.4.1'
+override :chef, version: '12.4.3'
 override :cacerts, version: '2015.09.02', source: { md5: '3e0e6f302bd4f5b94040b8bcee0ffe15' }
 override :openssl, version: '1.0.1p', source: { url: 'https://www.openssl.org/source/openssl-1.0.1p.tar.gz', md5: '7563e92327199e0067ccd0f79f436976' }