fix: remove transaction commit from multiple SO tags test

Remove commit() call that closes transaction prematurely.
Flush() provides sufficient visibility for verification queries
within the same transaction context.

Fixes test: TestFullGuildLifecycleWithAllConfigs::test_guild_with_multiple_sotags_and_users

Author: JacobCoffee

tests/integration/test_api_endpoints.py

@@ -332,7 +332,6 @@ async def test_guild_with_multiple_sotags_and_users(
             db_session.add(so_tag)
 
         await db_session.flush()
-        await db_session.commit()
 
         # Verify all tags exist
         result = await db_session.execute(select(SOTagsConfig).where(SOTagsConfig.guild_id == 8888))