Updates code to use preferred newer PHP function

This has been the recommendation for a long time, and it makes code easier to refactor
if everything does it the same way.

This fixes it to call the selectWhere in the BAO_Query, as apiv4 does. There is test
cover in the touched test.

The primary goal here is to get this logic out of core & to disabled this extension
on most sites with a view to moving the whole extension out of core in time

When cast to boolean by a conditional, these 2 functions behave identically, but str_contains is more readable

Regression was caused by  918e583a updating DAO::getSelectWhereClause
but not CRM_Contact_BAO_Query::generatePermissionClause. Turns out the code was being duplicated and
the latter could just call the former.

Follow-up to 918e583a - this correctly joins sub-arrays using OR

Before: selectWhereClause was limited to returning arrays of clauses which would be
joined with AND. They could not reference any other fields on the entity.

After: selectWhereClause can return sub-arrays which are joined with OR,
and can reference any field on the entity using {curly_brace} syntax.

Stricter type checking emits noisy deprecations if arrays are expected and strings are given.

This is an undefined property. Nothing accesses the mis-typed version....

Discovered this in the wild where an api3 Contact.getcount call for a particular smartgroup
was causing this. The smartgroup otherwise works fine.

Looking at the code, it's clear that getEntitySpecificJoins is supposed to return a string,
but in the case of civicrm_activity_contact it was returning from another function which may
return NULL. I have coalesced NULL to empty string.

This just mops up the handling, with the exception of the UFGroup function that
renders the profile (buildProfile) as we maybe need an upgrade script for that?