Harmony 1936: Add default job label to harmony-py jobs

[indiejames]

Jira Issue ID

HARMONY-1936

Description

This PR adds a default label of 'harmony-py' to jobs created with this library. It can be disabled by setting the environment variable EXCLUDE_DEFAULT_LABEL to "true".

Local Test Steps

1. Run the example/basic.ipynb notebook.
2. Verify that the created job has a 'harmony-py' label
3. set the EXCLUDE_DEFAULT_LABEL env var to "true"
4. Run the example notebook again.
5. Verify that the created job has no label.

PR Acceptance Checklist

• Acceptance criteria met
• Tests added/updated (if needed) and passing
• Documentation updated (if needed)

[vinnyinverso]

My only thought is that I wish there were a more centralized place to surface this information to the user, maybe via the readthedocs?

[indiejames]

My only thought is that I wish there were a more centralized place to surface this information to the user, maybe via the readthedocs?

Totally agree - was really frustrated by this. Didn't try to update the readthedocs stuff, because it looks that that is totally focused on the API, which is not really what this PR is about.