move await engine.dispose() to test client

tests/conftest.py

@@ -32,3 +32,6 @@ async def client() -> AsyncClient:
     ) as client:
         await start_db()
         yield client
+        # for AsyncEngine created in function scope, close and
+        # clean-up pooled connections
+        await engine.dispose()

the_app/database.py

@@ -31,6 +31,4 @@ async def get_db() -> AsyncGenerator:
         raise ex
     finally:
         await session.close()
-        # for AsyncEngine created in function scope, close and
-        # clean-up pooled connections
-        await engine.dispose()
+

the_app/main.py

@@ -17,6 +17,7 @@ app.include_router(nonsense_router)
 async def start_db():
     async with engine.begin() as conn:
         await conn.run_sync(Base.metadata.create_all)
+    await engine.dispose()
 
 
 @app.on_event("startup")