test_GenericAttentionLayer_extra_spatial_multi_head fix dims

#865

tests/test_TFNetworkRecLayer.py

@@ -7013,8 +7013,8 @@ def test_GenericAttentionLayer_extra_spatial_multi_head():
   net = TFNetwork(extern_data=ExternData(), config=Config({"debug_print_layer_output_template": True}))
   dec_time = SpatialDim("dec time")
   enc_time = SpatialDim("enc time")
-  num_heads = 8
-  heads_dim = FeatureDim("heads", dimension=num_heads)
+  heads_dim = FeatureDim("heads", dimension=8)
+  feat_dim = FeatureDim("feat", dimension=2048)
   kwargs = dict(
     name="att", network=net,
     weights=InternalLayer(
@@ -7024,14 +7024,13 @@ def test_GenericAttentionLayer_extra_spatial_multi_head():
     base=InternalLayer(
       name="enc_value", network=net,
       output=Data(
-        name='enc_value_output', shape=(None, num_heads, 2048), batch_dim_axis=1, auto_create_placeholders=True,
-        same_dim_tags_as={"t": enc_time})))
+        name='enc_value_output', dim_tags=[enc_time, batch_dim, heads_dim, feat_dim], auto_create_placeholders=True)))
   print("GenericAttentionLayer kwargs:")
   pprint(kwargs)
   kwargs["output"] = GenericAttentionLayer.get_out_data_from_opts(**kwargs)
   layer = GenericAttentionLayer(**kwargs)
   layer.output.sanity_check()
-  assert layer.output.shape == (num_heads, None, 2048) and layer.output.have_time_axis()
+  assert layer.output.shape == (heads_dim.dimension, None, feat_dim.dimension) and layer.output.have_time_axis()
   assert len(layer.output.size_placeholder) == 1
   assert list(layer.output.size_placeholder.values())[0] is layer.weights.output.size_placeholder[0]