SearchKit - Support field comparisons in HAVING clause

[colemanw]

Overview

Fixes broken field-comparison feature in SearchKit. It works for WHERE, but was not working for HAVING.

Before

This does not work (will return no results):

After

Works - above example will show all contacts whose first name equals their last name.

Technical Details

This fixes APIv4 to allow HAVING to refer to a column instead of a scalar value.

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[kapn1966]

Excellent! Thanks @colemanw. I can confirm that HAVING performs as expected now.

[colemanw]

Unrelated fail.