Add integer validation to import

[eileenmcnaughton]

Overview

Add integer validation to import

Before

passing in a non-integer to an integer field is not rejected in validate/getTransformedValues - it probably bounces later on though

After

Actively validate integers (once fields with option values have been resolved) in validate/getTransformedValues

Technical Details

I spotted that there used to be a security issue with the checks on contact id - that was fixed but it made me think we should harden this now while there is QA attention on imports.

Comments

[civibot]

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[eileenmcnaughton]

@totten @seamuslee001 @demeritcowboy @colemanw can we merge this asap - it's a security hardening & if we don't get it in for rc testing I might bottle out - if it DOES cause issues we can revert