fix (gradio-pdf): preview not displaying CJK characters

pyproject.toml

@@ -27,7 +27,7 @@ dependencies = [
     "opencv-python-headless",
     "tencentcloud-sdk-python",
     "pdfminer.six>=20240706",
-    "gradio_pdf",
+    "gradio_pdf>=0.0.21",
     "pikepdf",
 ]