sql: inlined UDFs do not report error CONTEXT

When UDF bodies are inlined into their calling statements, they lose the ability to report error CONTEXT. Here's an example:

```sql
-- with a call to random() the UDF is not inlined, and is able to add CONTEXT to errors
CREATE FUNCTION f_not_inlined(n INT) RETURNS INT AS $$
BEGIN
IF n < 0 THEN
RETURN 0;
END IF;
RETURN 1 / n + (random() * 0)::INT;
END
$$ LANGUAGE PLpgSQL;
SELECT f_not_inlined(0);
-- ERROR: division by zero
-- SQLSTATE: 22012
-- CONTEXT: PL/pgSQL function f_not_inlined(bigint) line 2 at IF

-- without random() the UDF is inlined into the calling SELECT and cannot add CONTEXT to errors
CREATE FUNCTION f_inlined(n INT) RETURNS INT AS $$
BEGIN
IF n < 0 THEN
RETURN 0;
END IF;
RETURN 1 / n;
END
$$ LANGUAGE PLpgSQL;
SELECT f_inlined(0);
-- ERROR: division by zero
-- SQLSTATE: 22012
```

Jira issue: CRDB-65744