Reset autocommit to True (temporarily)

A deadlock has happened at least on two occasions which may be related
to the autocommit setting recently set to False. Resetting this to True
until we can figure out what's causing the deadlock and fix it.

lib/galaxy/model/base.py

@@ -59,7 +59,7 @@ def transaction(session: Union[scoped_session, Session, "SessionlessContext"]):
 class ModelMapping(Bunch):
     def __init__(self, model_modules, engine):
         self.engine = engine
-        self._SessionLocal = sessionmaker(autoflush=False, autocommit=False)
+        self._SessionLocal = sessionmaker(autoflush=False, autocommit=True)
         versioned_session(self._SessionLocal)
         context = scoped_session(self._SessionLocal, scopefunc=self.request_scopefunc)
         # For backward compatibility with "context.current"