`SET CONSTRAINTS` fails with an internal error

On Doltgres 1.3.2, `SET CONSTRAINTS` fails for both `IMMEDIATE` and `DEFERRED` modes.

### Repro

```sql
BEGIN;
SET CONSTRAINTS ALL IMMEDIATE;
ROLLBACK;

BEGIN;
SET CONSTRAINTS ALL DEFERRED;
ROLLBACK;
```

Both commands produce:

```text
ERROR: unknown statement type encountered: `*tree.SetConstraints`
SQLSTATE: XX000
```

Named constraints fail the same way:

```sql
CREATE TABLE parent_example (
id integer PRIMARY KEY
);

CREATE TABLE child_example (
id integer PRIMARY KEY,
parent_id integer CONSTRAINT child_parent_fk
REFERENCES parent_example(id)
DEFERRABLE INITIALLY DEFERRED
);

BEGIN;
SET CONSTRAINTS child_parent_fk IMMEDIATE;
ROLLBACK;
```

Start by running the supplied BEGIN, SET CONSTRAINTS, and ROLLBACK repros, then trace handling of the `SET CONSTRAINTS` statement and the `tree.SetConstraints` type. Done means both ALL and named constraints work in IMMEDIATE and DEFERRED modes without the internal error.

Written by the indexing model from the issue text.