Updated the now deprecated Series.replace() to Series.cat.rename_cate…

…gories()

Signed-off-by: S.J. Guillot <[email protected]>

yasa/hypno.py

@@ -482,7 +482,7 @@ def as_int(self):
         Name: Stage, dtype: int16
         """
         # Return as int16 (-32768 to 32767) to reduce memory usage
-        return self.hypno.replace(self.mapping).astype(np.int16)
+        return self.hypno.cat.rename_categories(self.mapping).astype(np.int16)
 
     def consolidate_stages(self, new_n_stages):
         """Reduce the number of stages in a hypnogram to match actigraphy or wearables.