ENH: Adding ITAB file reader

Describe the new feature or enhancement

We would like to add the ITAB raw file reader to MNE-Python. @vpizzella made a first draft of the reader and I am prepping it following your guidelines with tests and linting.
I have a bunch of question regarding the management of testing data and tests:

1. I noticed that data is included in another repo, should I open a PR also in this repo?
2. Is there a size limit of the files?
3. Is it better a file that includes all features implemented (and tested) or it is better a set of files?
4. I used a matlab (fieldtrip) file to test whether the reader reads the same numbers, is it correct or is there any other strategy?

Describe your proposed implementation

A first draft of the implementation can be found here, but it needs linting and so on.

Describe possible alternatives

We followed other readers implementation, so it is similar to other readers and maybe optimal.

Additional context

No response

Start by reviewing the draft reader in mne/io/itab and comparing it with the other reader implementations referenced in the issue. Clarify the testing-data repository, file-size, fixture, and MATLAB/FieldTrip validation questions before proceeding. Done means the ITAB reader is linted and covered by tests using appropriate test data.