Draft: Make 'file_format' optional

[aaronsteers]

Problem

WIP. Resolves #188

Proposed changes

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If it fixes a bug or resolves a feature request, be sure to link to that issue.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

• Description above provides context of the change
• I have added tests that prove my fix is effective or that my feature works
• Unit tests for changes (not needed for documentation changes)
• CI checks pass with my changes
• Bumping version in setup.py is an individual PR and not mixed with feature or bugfix PRs
• Commit message/PR title starts with [AP-NNNN] (if applicable. AP-NNNN = JIRA ID)
• Branch name starts with AP-NNN (if applicable. AP-NNN = JIRA ID)
• Commits follow "How to write a good git commit message"
• Relevant documentation is updated including usage instructions

[aaronsteers]

@koszti - I have a start here but I haven't tested yet. Do you mind enabling the CI workflow for this pipeline? Thanks!

[koszti]

@koszti - I have a start here but I haven't tested yet. Do you mind enabling the CI workflow for this pipeline? Thanks!

Enabled. Please note that only the unit tests will run from your PR. Integration tests require a snowflake instance that's not available for PRs from forked repos. Can you please run integration tests locally by setting the env vars that defined here and point to your snowflake account?