[Feature Request]: SharepointReader cannot read root folder of drive

[CraftingLevi]

Feature Description

As a user, I want to load files from the root folder of the Sharepoint drive
So that I can index these files and all files in subfolders in a Sharepoint drive
In order to use these files in LLM use cases by transforming them into Document objects.

Reason

Currently, the user cannot provide a valid argument to SharepointReader to get the content of the root folder.

Value of Feature

After implementing this feature, the user can:

• The user can load files directly in the root folder of a Sharepoint Drive