Fix user check for jira ticketing

[chi-yelp]

Problem

paasta CLI commands such as paasta validate, paasta mark-for-deployment are blocked by the jira ticket check since they call the get_spark_config while trying the build the Tron configs.

More details in: https://github.yelpcorp.com/sysgit/srv-configs/pull/44869

Solution

Use the user explicitly passed from get_spark_conf parameters for jira ticketing check, instead of reading from environment variables.

Test

• Unit tests
• Hard-coding jira_ticket.enabled to true and build a whl and install to local paasta repo to test the following commands:

./.tox/py38-linux/bin/paasta validate -y ~/projects/sysgit/yelpsoa-configs -s spark
./tox/py38-linux/bin/paasta spark-run --aws-profile=dev --cmd bash

[nemacysts]

TICKET_NOT_REQUIRED_USERS = {
    'batch',  # non-human spark-run from batch boxes
    'TRON',  # tronjobs that run commands like paasta mark-for-deployment
    None,  # placeholder for being unable to determine user
}

[nemacysts]

also, I think this makes my next question a lot clearer: do we need to add UNSPECIFIED to this set?

[chi-yelp]

It's for keeping the user pod label spark.yelp.com/user for the metrics / pod search, specific to _get_k8s_spark_env(). I changed the constant name to USER_LABEL_UNSPECIFIED for clarification

[sidsatyelp]

How do we verify that this fixes the issue for paasta mark-for-deployment ?
Afaik, that paasta subcommand has no dry-run option.

[chi-yelp]

How do we verify that this fixes the issue for paasta mark-for-deployment ? Afaik, that paasta subcommand has no dry-run option.

Perhaps @nemacysts will have a better idea. On the other hand, I think if paasta validate passes there shouldn't be a problem for paasta mark-for-deployment, as they construct tron configs in the same way