Moves api doc jobs to the api-jobs.yaml file.

No other changes, just moving.

Change-Id: Ia418f630d28640ed891a7b93bed4e72f08fa0f31
Reviewed-on: https://review.openstack.org/25145
Reviewed-by: James E. Blair <corvus@inaugust.com>
Reviewed-by: Elizabeth Krumbach <lyz@princessleia.com>
Approved: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Tested-by: Jenkins