Allow to run etl:rerun_main for a single date

[AgaDufrat]

We are often asked to do this by performance analysts when data didn't appear in BigQuery before the import run.

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Review Checklist

• [ ] Changes in scope.
• [ ] Added/updated unit tests.
• [ ] Added/updated feature tests.
• [ ] Added/updated relevant documentation.
• [ ] Added to Trello card.

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