add failing tests for TimeSeriesTransformer

The deserialization of the `TimeSeriesTransformer` is broken, but it
went undetected as this network is not included in the tests yet. This
commit adds the network, but does not resolve the deserialization
problems yet.

Regards #423

Author: vpratz

tests/test_networks/conftest.py

@@ -119,6 +119,13 @@ def time_series_network(summary_dim):
     return TimeSeriesNetwork(summary_dim=summary_dim)
 
 
+@pytest.fixture(scope="function")
+def time_series_transformer(summary_dim):
+    from bayesflow.networks import TimeSeriesTransformer
+
+    return TimeSeriesTransformer(summary_dim=summary_dim)
+
+
 @pytest.fixture(scope="function")
 def set_transformer(summary_dim):
     from bayesflow.networks import SetTransformer
@@ -133,7 +140,9 @@ def deep_set(summary_dim):
     return DeepSet(summary_dim=summary_dim)
 
 
-@pytest.fixture(params=[None, "time_series_network", "set_transformer", "deep_set"], scope="function")
+@pytest.fixture(
+    params=[None, "time_series_network", "time_series_transformer", "set_transformer", "deep_set"], scope="function"
+)
 def summary_network(request, summary_dim):
     if request.param is None:
         return None