[ENH] Remove attrs dependency

[Alex-JG3]

Reference Issues/PRs

Closes #5290.

What does this implement/fix? Explain your changes.

• Replaces attrs with dataclasses in the igts and ggs modules of the annotation module.

Does your contribution introduce a new dependency? If yes, which one?

No, but it removes attrs as a dependency for the annotation module.

What should a reviewer concentrate their feedback on?

I would like feedback on the get_params methods for the InformationGainSegmentation and GreedyGaussianSegmentation classes. Using attrs, one can easily filter attributes where init is False. That is not so easy with dataclasses so I filtered the unwanted attributes manually. We could have tags in the GSS and IGTS classes called something like __attributes_to_ignore__ which would be a list of attributes to ignore in the get_params methods. But, since the pattern used for GGS and IGTS is likely going to change soon, I didn't think it necessary to use the tags approach.

Did you add any tests for the change?

No, but I changed the test_ggs.py and test_igts.py files to reflect the refactoring in ggs.py and igts.py respectively.

Any other comments?

Can attrs be removed from the all_extras and all_extras_pandas2 lists of dependencies in pyproject.toml?

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[fkiraly]

Thanks! This seems to remove the unnecessary dependency completely.

[fkiraly]

We should also remove it from the all_extras dependency set.

[fkiraly]

there's one more, in all_extras_pandas2 ... just do a repo search for attrs, and let's check if it is entirely gone.

[fkiraly]

Looks good now!

[fkiraly]

I would like feedback on the get_params methods for the
InformationGainSegmentation and GreedyGaussianSegmentation classes.

Looking at this, I think the methods are not conformant with the usual expectation that they return only and exactly the __init__ parameters. Naively, I would simply delete get_params and set_params to use the default from BaseObject.

Fitted parameters, if any, should get exposed via get_fitted_params.