fixup initial provisioning of aio postgres db (#2571)

fixes #2570

libs/checkpoint-postgres/langgraph/checkpoint/postgres/aio.py

@@ -5,7 +5,6 @@
 
 from langchain_core.runnables import RunnableConfig
 from psycopg import AsyncConnection, AsyncCursor, AsyncPipeline, Capabilities
-from psycopg.errors import UndefinedTable
 from psycopg.rows import DictRow, dict_row
 from psycopg.types.json import Jsonb
 from psycopg_pool import AsyncConnectionPool
@@ -81,17 +80,15 @@ async def setup(self) -> None:
         the first time checkpointer is used.
         """
         async with self._cursor() as cur:
-            try:
-                results = await cur.execute(
-                    "SELECT v FROM checkpoint_migrations ORDER BY v DESC LIMIT 1"
-                )
-                row = await results.fetchone()
-                if row is None:
-                    version = -1
-                else:
-                    version = row["v"]
-            except UndefinedTable:
+            await cur.execute(self.MIGRATIONS[0])
+            results = await cur.execute(
+                "SELECT v FROM checkpoint_migrations ORDER BY v DESC LIMIT 1"
+            )
+            row = await results.fetchone()
+            if row is None:
                 version = -1
+            else:
+                version = row["v"]
             for v, migration in zip(
                 range(version + 1, len(self.MIGRATIONS)),
                 self.MIGRATIONS[version + 1 :],