[Kubernetes] Restrict final pod name to ~200 symbols

[aivanou]

We need to restrict the max pod name produced by the torchx kubernetes-scheduler to the max length allowed length. If we do not do this, it would be hard to debug these kind of jobs.

[aivanou]

It seems it got fixed in the latest volcano version, now volcano produces an error:

Reason: Bad Request
HTTP response headers: HTTPHeaderDict({'Audit-Id': '28f9da0c-046f-41c5-b26e-a615663b998b', 'Cache-Control': 'no-cache, private', 'Content-Type': 'application/json', 'Date': 'Tue, 02 Nov 2021 19:24:22 GMT', 'Content-Length': '389'})
HTTP response body: {"kind":"Status","apiVersion":"v1","metadata":{},"status":"Failure","message":"admission webhook \"validatejob.volcano.sh\" denied the request: create pod with name torchx-cv-trainer-tf7xpsc4ndcmcd-my-torchx-cv-trainer-awesome-worker-0-0 validate failed [name part must be no more than 63 characters]; unable to find job queue: queues.scheduling.volcano.sh \"test\" not found","code":400}