Allow for CI_JOB_TOKEN to play manual jobs

Description

I'd like to be able to use the jobs play API to play manual jobs in the same pipeline. I understand a Private-Token would work, but I'd like to use the CI_JOB_TOKEN, so the user who triggered the pipeline is maintained.

Proposal

Please allow for the CI_JOB_TOKEN to be used to authenticate the following endpoint: POST /projects/:id/jobs/:job_id/play