fix tf policy for ghosts

ml-agents/mlagents/trainers/policy/tf_policy.py

                 tf.GraphKeys.TRAINABLE_VARIABLES, scope="lstm"
             )  # LSTMs need to be root scope for Barracuda export
             # Create assignment ops for Ghost Trainer
-            self.init_load_weights()
 
         self.inference_dict = {
             "action": self.output,
         # We do an initialize to make the Policy usable out of the box. If an optimizer is needed,
         # it will re-load the full graph
         self.initialize()
+        self.init_load_weights()
 
     def _create_encoder(
         self,