Revert "Ensure the path is case sensitive"

[freekmurze]

Reverts spatie/flysystem-dropbox#10 because

• PR contains no tests and is hard to refactor
• unsure if the PR fixes the whole problem
• unsure if it's the flysystem driver's role to fix this.

[jpkleemans]

The problem still exists. Random folders won't load their contents using listContents. Is there any news on this?