fix: update import statement for resources to improve compatibility with Python 3.9+

Author: thawancomt

python/ctranslate2/__init__.py

@@ -9,10 +9,10 @@
 
     # Adressing python 3.9 < version
     try:
-        from importlib import resources
+        from importlib.resources import files
 
         # Fixed the pkg_resources depreciation
-        package_dir = str(resources.files(module_name))
+        package_dir = str(files(module_name))
     except ImportError:
         import pkg_resources