Fix SB 1.0 compatibility

See: https://github.com/speechbrain/speechbrain/issues/2604

This model was trained with `causal: True` (the default), but this functionality was broken pre-1.0.
Upon checking, the `TransformerASR` for this model doesn't seem to have anything else affected by the switch from `causal: True` to `causal: False`.

hyperparams.yaml

@@ -64,6 +64,7 @@ Transformer: !new:speechbrain.lobes.models.transformer.TransformerASR.Transforme
     dropout: !ref <transformer_dropout>
     activation: !ref <activation>
     normalize_before: False
+    causal: False
 
 ctc_lin: !new:speechbrain.nnet.linear.Linear
     input_size: !ref <d_model>