[TTS] DE Multi-Speaker FastPitch HiFiGAN Tokenization Error
When following the basic instructions [here](https://catalog.ngc.nvidia.com/orgs/nvidia/teams/nemo/models/tts_de_fastpitch_multispeaker_5): 
just replace the text promp with: "hallo wie geht es ihnen?" - German for "Hello, how are you doing?"

This occours: 

[hallo wie geht es ihnen?] contains unknown char: [g]. Symbol will be skipped.

**Expected behavior**

The letter "g" is commonly used in the German alphabet and is essential to pronunciation of certain words. It seems that this issue is related to the trained models that are provided under that link.


