build: remove unused dependencies

requirements.txt

@@ -7,8 +7,7 @@ torch>=2.1
 torchaudio
 soundfile>=0.12.0
 librosa>=0.10.0
-scikit-learn>=1.3.0
-numba>=0.57.0;python_version>="3.9"
+numba>=0.57.0
 inflect>=5.6.0
 tqdm>=4.64.1
 anyascii>=0.3.0
@@ -38,7 +37,6 @@ hangul_romanize
 gruut[de,es,fr]==2.2.3
 # deps for korean
 jamo
-nltk
 g2pkk>=0.1.1
 # deps for bangla
 bangla
@@ -50,6 +48,5 @@ transformers>=4.33.0
 #deps for bark
 encodec>=0.1.1
 # deps for XTTS
-unidecode>=1.3.2
 num2words
 spacy[ja]>=3