[Ref] [Import] Cleanup cleanup on old tables for form re-submission

[eileenmcnaughton]

Overview

Cleanup cleanup on old tables for form re-submission

Before

The form needs to know about the table name

After

Responsibility is with the dataSource - the data source flushes the table, and the table is explicity flushed when it's clear the form is being re-submitted rather than in a hidden magic place

Technical Details

Comments

[civibot]

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[colemanw]

OK, test coverage looks solid.