Remove gate-cookbook-openstack-compute-chef-style from compute gating

The Chef cookbooks are in the process of replacing our style gating use of
Tailor with Rubocop. Those patches are slowly working their way through Gerrit,
but the cookbook-openstack-compute cookbook has tailor checking as part of its
gate. It is the only Chef cookbook with this gate, so we will temporarily remove
it and once the Rubocop cleanups are in place we will restore this check to the
compute cookbook and all of the others.

Change-Id: I0b9b833f1d71604510b7dd2c6b563031e4355b45
Merge "Remove gate-cookbook-openstack-compute-chef-style from compute gating"