lower transaction isolation for workflow create to level repeatable r…

…ead to avoid concurrency error due to level serializable being overly strict

Signed-off-by: Kelly Deng <[email protected]>

db/workflow.go

@@ -33,7 +33,7 @@ var (
 
 // CreateWorkflow creates a new workflow
 func (d TinkDB) CreateWorkflow(ctx context.Context, wf Workflow, data string, id uuid.UUID) error {
-	tx, err := d.instance.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelSerializable})
+	tx, err := d.instance.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelRepeatableRead})
 	if err != nil {
 		return errors.Wrap(err, "BEGIN transaction")
 	}