fix(db): run schema-level grants against the shared database, not postgres

src/lib/db/dbctl_integration_test.go

@@ -68,7 +68,7 @@ func TestSyncAuthorizationIntegration(t *testing.T) {
 	}
 	assert := func(t *testing.T, sql, contains string) {
 		t.Helper()
-		out, code, err := c.execPSQL(context.Background(), id, sql)
+		out, code, err := c.execPSQL(context.Background(), id, "postgres", sql)
 		if err != nil || code != 0 {
 			t.Fatalf("check %q failed (exit %d, err %v): %s", sql, code, err, out)
 		}