Fix full group by in search builder when using tags

[mattwire]

Overview

When using search builder and searching by tag only a single contact is displayed in the search results but the count is correct (eg 49). When changing the number of displayed per page a mysql full group by error occurs as there is no group by clause (for contact_a.id).

Example search using demo data:

Before

Search builder does not display results properly when searching by tag.

After

Search builder does display results properly when searching by tag.

Technical Details

This is another fullgroupby issue.

Comments

@seamuslee001 Tagging you as the resident fullgroupby expert!

[civibot]

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[mattwire]

Test failure looks related, but I'm a bit out of my depth now!

[eileenmcnaughton]

@mattwire I think we'd want a test on this one - I'm totally OK with the use of disableFullGroupBy when a query might not support it as a fix as long as it's in conjunction with a test

[mattwire]

Fixed via #13533

[eileenmcnaughton]

Ah dang I didn't draw the connection with this PR when I was digging into that issue. Anyway I think we are good now