Adding support for databricks spark python and submit tasks.

[siddartha-ravichandran]

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The Databricks Jobs API, which exposes the Runs Submit API, documented here: https://docs.databricks.com/dev-tools/api/latest/jobs.html#runs-submit, supports the following 4 tasks: spark_jar_task, notebook_task, spark_python_task and spark_submit_task. The databricks operator which exposes this functionality however did not support the latter 2 (spark_python_task and spark_submit_task). This PR adds support for these 2 tasks.

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[boring-cyborg]

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[boring-cyborg]

Awesome work, congrats on your first merged pull request!