docs: Correct return type in docstring (#22597)

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- [x] **PR message**: 
- **Description:** This PR corrects the return type in the docstring of
the `docs/api_reference/create_api_rst.py/_load_package_modules`
function. The return type was previously described as a list of

Co-authored-by: suganthsolamanraja <suganth.solamanraja@techjays..com>

docs/api_reference/create_api_rst.py

@@ -128,11 +128,11 @@ def _load_package_modules(
     of the modules/packages are part of the package vs. 3rd party or built-in.
 
     Parameters:
-        package_directory: Path to the package directory.
-        submodule: Optional name of submodule to load.
+        package_directory (Union[str, Path]): Path to the package directory.
+        submodule (Optional[str]): Optional name of submodule to load.
 
     Returns:
-        list: A list of loaded module objects.
+        Dict[str, ModuleMembers]: A dictionary where keys are module names and values are ModuleMembers objects.
     """
     package_path = (
         Path(package_directory)