Avoid unnecessary observable notifications of Iterable or Map fields

Describe the changes proposed in this Pull Request.

Following up on pr https://github.com/mobxjs/mobx.dart/pull/844, perform deep equals if value is Iterable or Map.

Pull Request Checklist

[x] If the changes are being made to code, ensure the version in pubspec.yaml is updated.
[x] Increment the major/minor/patch/patch-count, depending on the complexity of change
[x] Add the necessary unit tests to ensure the coverage does not drop
[x] Update the Changelog to include all changes made in this PR, organized by version
[x] Run the melos run set_version command from the root directory
[x] Include the necessary reviewers for the PR
[x] Update the docs if there are any API changes or additions to functionality