sql: remove slow functions from TestRandomSyntaxFunctions

Previously, we could easily timeout running slower,
functions in the random syntax functions test. We
attempted to minimize this risk with resettable timeouts
which helped, but libpq has limited support for cancellation,
so we need to fully pull these out. To address this,
this patch will remove:
crdb_internal.revalidate_unique_constraints_in_all_tables
and crdb_internal.validate_ttl_scheduled_jobs from testing.

Fixes: #107929
Release note: None

pkg/sql/tests/rsg_test.go

@@ -200,6 +200,16 @@ func (db *verifyFormatDB) execWithResettableTimeout(
 					return &nonCrasher{sql: sql, err: err}
 				}
 				return nil
+			case <-ctx.Done():
+				// Sanity: The context is cancelled when the test is about to
+				// timeout. We will log whatever statement we're waiting on for
+				// debugging purposes. Sometimes queries won't respect
+				// cancellation due to lib/pq limitations.
+				t.Logf("Context cancelled while executing: %q", sql)
+				// We will intentionally retry, which will us to wait for the
+				// go routine to complete above to avoid leaking it.
+				retry = true
+				return nil
 			case <-time.After(targetDuration):
 				db.mu.Lock()
 				defer db.mu.Unlock()
@@ -357,7 +367,9 @@ func TestRandomSyntaxFunctions(t *testing.T) {
 				case "crdb_internal.reset_sql_stats",
 					"crdb_internal.check_consistency",
 					"crdb_internal.request_statement_bundle",
-					"crdb_internal.reset_activity_tables":
+					"crdb_internal.reset_activity_tables",
+					"crdb_internal.revalidate_unique_constraints_in_all_tables",
+					"crdb_internal.validate_ttl_scheduled_jobs":
 					// Skipped due to long execution time.
 					continue
 				}