Read a column found in two tables from the first table inside a built-in function, as before #2619 - #2929

This adjusts a breaking change we merged by accident in #2619. That PR lets a bare column inside a built-in function (UPPER, LENGTH, TRIM and the rest) resolve to the table that has it, which fixes #2615. But a column found in both joined tables now throws Cannot resolve column "name" because it exists in two source tables, where 4.22.0 read it from the first table.

CREATE TABLE a (id INT, name STRING);
CREATE TABLE b (id INT, name STRING);
SELECT UPPER(name) FROM a JOIN b ON a.id = b.id; -- 4.22.0 reads a.name, develop throws

With this change, such a column reads the first table again inside a built-in function, and a column of one table keeps the fix from #2619. Test F in test/test2615.js covers JOIN, LEFT JOIN, a comma join and WHERE. The full suite passes.

Rejecting the ambiguous column is the right behaviour in the long run, and #2928 tracks it for the next major version.