[TTS] Convert entry from UTF-16 to UTF-8
Signed-off-by: Jocelyn Huang <jocelynh@nvidia.com>

# What does this PR do ?

Updates the DÉJÀ entry in CMUdict to the correct encoding (UTF-8), as mentioned in #3594.
**Collection**: TTS

# Changelog 
Bytes `D\xc9J\xc0` updated to `D\xc3\x89J\xc3\x80`.

**PR Type**:
- [ ] New Feature
- [x] Bugfix
- [ ] Documentation