Resolve label deletion issue

[sungmanc]

Summary

If user add/delete the label, the circumstances below could be happen.

• Multi-class --> Multi-class
• Multi-class --> Multi-label
• Multi-class --> H-label
• Multi-label --> Multi-class
• Multi-label --> Multi-label
• Multi-label --> H-label
• H-label --> Multi-class
• H-label --> Multi-label
• H-label --> H-label

To consider the above cases, I edited the test datasets and added integration tests to check the class decremental case (label deletion). It is not perfect and I don't want to change many things since it is a quick workaround.

Need more precise test cases to consider the label deletion, for further use.

How to test

Checklist

• I have added unit tests to cover my changes.​
• I have added integration tests to cover my changes.​
• I have added e2e tests for validation.
• I have added the description of my changes into CHANGELOG in my target branch (e.g., CHANGELOG in develop).​
• I have updated the documentation in my target branch accordingly (e.g., documentation in develop).
• I have linked related issues.

License

• I submit my code changes under the same Apache License that covers the project.
  Feel free to contact the maintainers if that's a concern.
• I have updated the license header for each file (see an example below).

# Copyright (C) 2023 Intel Corporation
# SPDX-License-Identifier: Apache-2.0

[sungmanc]

http://validationreports.sclab.intel.com:8004/reports/build_number_report?test_session_build_number=IMPTOps-66139&environment=mclx33

[eunwoosh]

Thanks for your work! Doesn't this change also have to apply to other versions?