docs: add PostgreSQL procedure to supported objects (#503)

Author: rebelice

content/docs/change-database/synchronize-schema.md

@@ -28,13 +28,13 @@ The overall workflow:
 
 ## Supported Objects
 
-| Database              | Objects                                                                                                                            |
-| --------------------- | ---------------------------------------------------------------------------------------------------------------------------------- |
-| MySQL                 | `Table`, `Index`, `Constraint`, `View`, `Event`, `Trigger`, `Function`, `Procedure`                                                |
-| PostgreSQL            | `Schema`, `Table`, `Index`, `Constraint`, `View`, `Materialized View`, `Sequence`, `Extension`, `Function`, `Trigger`, `Enum Type` |
-| TiDB                  | `Table`, `Index`, `Constraint`, `View`                                                                                             |
-| Oracle                | `Table`, `Index`, `Constraint`                                                                                                     |
-| Microsoft SQL Server  | `Table`, `Index`, `Constraint`                                                                                                     |
+| Database              | Objects                                                                                                                                         |
+| --------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------- |
+| MySQL                 | `Table`, `Index`, `Constraint`, `View`, `Event`, `Trigger`, `Function`, `Procedure`                                                             |
+| PostgreSQL            | `Schema`, `Table`, `Index`, `Constraint`, `View`, `Materialized View`, `Sequence`, `Extension`, `Function`, `Procedure`, `Trigger`, `Enum Type` |
+| TiDB                  | `Table`, `Index`, `Constraint`, `View`                                                                                                          |
+| Oracle                | `Table`, `Index`, `Constraint`                                                                                                                  |
+| Microsoft SQL Server  | `Table`, `Index`, `Constraint`                                                                                                                  |
 
 ## How to use