📚[DOC]: Fix code block in IO userguide

[NickGeneva]

How would you describe the priority of this documentation request

Medium

Describe the incorrect/future/missing documentation

Second code block seems to of gotten messed up. https://nvidia.github.io/earth2studio/userguide/components/io.html#io-backend-interface

Should use comments to guide code blocks like: https://github.com/NVIDIA/earth2studio/blob/main/earth2studio/run.py#L38

And https://github.com/NVIDIA/earth2studio/blob/main/docs/userguide/components/datasources.md?plain=1#L69