ActivityHandler unit tests and building/installing packages

[axelsrz]

This pull request includes several updates to the CI/CD pipeline and improvements to the ActivityHandler class in the Botbuilder library. The most important changes involve adding new dependencies, building and installing packages, refactoring methods, and adding new tests.

CI/CD Pipeline Enhancements:

• Updated steps: in .azdo/ci-pr.yaml and .github/workflows/python-package.yml to include pytest-asyncio and build in the list of dependencies. [1] [2]
• Added steps to build and install packages from the dist directory in both .azdo/ci-pr.yaml and .github/workflows/python-package.yml. [1] [2]

Botbuilder Library Improvements:

• Refactored the on_conversation_update_activity method in activity_handler.py to simplify the logic for handling members added or removed.
• Modified the _create_invoke_response method to handle cases where the body is None in activity_handler.py.
• Updated _get_adaptive_card_invoke_value to directly access invoke_value.action.type instead of using get method.

Testing Enhancements:

• Added comprehensive tests for ActivityHandler in test_activity_handler.py to cover various activity types and scenarios.

Core Model Updates:

• Replaced the Config class with ConfigDict in agents_model.py and entity.py for better configuration management. [1] [2] [3]