Enforce utf-8 on all file r/w
# Bugfix
- Enforce UTF-8 on all file reading and writing. Fixes a bug with some locales not enforcing utf 8.
- If you are still facing Unicode errors, you have to pass `LC_ALL=en_US.UTF-8` before launching your python command. 

Fixes https://github.com/NVIDIA/NeMo/issues/3452