Fix local docker invalid container name created by trimming #958
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Change:
123.-_app-id123456docker.errors.APIError: 400 Client Error for http+docker://localhost/v1.41/containers/create?name=.-_app-id123456-b2hcqzf4bxkjhd-role-name-0: Bad Request ("Invalid container name (.-_app-id123456-b2hcqzf4bxkjhd-role-name-0), only [a-zA-Z0-9][a-zA-Z0-9_.-] are allowed")Test plan:
pytest torchx/schedulers/test/docker_scheduler_test.py=> 16 passed in 33.68s