unpin cython version and commentout pyworld in audio.py causing dep

issues

TTS/utils/audio.py

@@ -292,6 +292,7 @@ class AudioProcessor(object):
         return pad // 2, pad // 2 + pad % 2
 
     ### Compute F0 ###
+    # TODO: pw causes some dep issues
     # def compute_f0(self, x):
     #     f0, t = pw.dio(
     #         x.astype(np.double),

requirements.txt

@@ -21,5 +21,5 @@ cardboardlint==1.3.0
 pylint==2.5.3
 gdown
 umap-learn
-cython==0.29.20 # > 0.29.20 breaks pyworld installation with the min numpy req of Tensorflow 2.4.1
+cython
 pyyaml