fix windows path to string bug (#70)

Co-authored-by: Michael Kali <[email protected]>

Author: mkali-weizmann

manim_voiceover/services/base.py

@@ -110,8 +110,8 @@ def _wrap_generate_from_text(self, text: str, path: str = None, **kwargs) -> dic
             adjusted_path = split_path[0] + "_adjusted" + split_path[1]
 
             adjust_speed(
-                Path(self.cache_dir) / dict_["original_audio"],
-                Path(self.cache_dir) / adjusted_path,
+                str(Path(self.cache_dir) / dict_["original_audio"]),
+                str(Path(self.cache_dir) / adjusted_path),
                 self.global_speed,
             )
             dict_["final_audio"] = adjusted_path