Update app.py

...to avoid overfitting

app.py

@@ -23,7 +23,7 @@ alphabet, tacotron_net, tacotron_config = load_tacotron_model(
 )
 
 wavegru_config, wavegru_net = load_wavegru_net(
-    "./wavegru.yaml", "./wavegru_vocoder_tpu_gta_preemphasis_pruning_0800000.ckpt"
+    "./wavegru.yaml", "./wavegru_vocoder_tpu_gta_preemphasis_pruning_0400000.ckpt"
 )
 
 wave_cpp_weight_mask = extract_weight_mask(wavegru_net)