Contribution import - simplify error handling

[eileenmcnaughton]

Overview

Contribution import - simplify error handling

Before

Lots of handling, call to summary - but this has been removed from the other imports as it validates the rows - but that has already been done by this point, and the table has been updated with the results - so the ones that failed will not load

After

Rely on the catch block, removed summary call

Technical Details

Comments

@colemanw should be straight forward

[civibot]

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