[fix] star-transformer position embedding

fastNLP/modules/encoder/star_transformer.py

@@ -69,7 +69,7 @@ class StarTransformer(nn.Module):
         smask = torch.cat([torch.zeros(B, 1, ).byte().to(mask), mask], 1)
 
         embs = data.permute(0, 2, 1)[:, :, :, None]  # B H L 1
-        if self.pos_emb and False:
+        if self.pos_emb:
             P = self.pos_emb(torch.arange(L, dtype=torch.long, device=embs.device) \
                              .view(1, L)).permute(0, 2, 1).contiguous()[:, :, :, None]  # 1 H L 1
             embs = embs + P