feat: implemented MultiReader

[fernandoGubiMarques]

Describe your changes

Implemented a reader class to compile the output of multiple readers.

Checklist before requesting a review

• I have performed a self-review of my code.
• I have added tests to this funtionality.
• All tests are passing.
• I have updated the documentation as needed.
• I have followed the project's coding guidelines.

[GabrielBG0]

@fernandoGubiMarques How do you think this new reader could be used and why do you think it is important for us to have it?

[fernandoGubiMarques]

This class is crucial for reading from more than one source which contain homologous information. For example, in the context of seismic segmentation, two seismic attributes for the same patch of subsoil stored in separate .npy files can be read from using PatchedArrayReader, but their items remain disconnected.

Through this composite reader, the i-th item of each of the PatchedArrayReaders stacked together according to a collate_fn function."""

[GabrielBG0]

sure

[GabrielBG0]

LGTM