Hello,

Slack has released updates to its library and we can start using it for it. 

We especially like one change.

> slack_sdk has no required dependencies. This means aiohttp is no longer automatically resolved.

I've looked through the documentation and it doesn't look like a difficult task, but I think it's still worth testing.
More info: https://slack.dev/python-slack-sdk/v3-migration/index.html#from-slackclient-2-x

Best regards,
Kamil Breguła
setup.py
"""
    The setuptools.Distribution subclass with Airflow specific behaviour
    The reason for pylint: disable=signature-differs of parse_config_files is explained here:
    https://github.com/PyCQA/pylint/issues/3737
    """
    def parse_config_files(self, *args, **kwargs):  
        """
        Ensure that when we have been asked to install providers from sources
        that we don't *also* try to install those providers from PyPI.
        Also we should make sure that in this case we copy provider.yaml files so that
        Providers manager can find package information.
        """
        super().parse_config_files(*args, **kwargs)
        if os.getenv(INSTALL_PROVIDERS_FROM_SOURCES) == 'true':
            self.install_requires = [  
                req for req in self.install_requires if not req.startswith('apache-airflow-providers-')
            ]
            provider_yaml_files = glob.glob("airflow/providers/**/provider.yaml", recursive=True)
            for provider_yaml_file in provider_yaml_files:
                provider_relative_path = relpath(provider_yaml_file, os.path.join(my_dir, "airflow"))
                self.package_data['airflow'].append(provider_relative_path)
        else:
            self.install_requires.extend(
                [get_provider_package_from_package_id(package_id) for package_id in PREINSTALLED_PROVIDERS]
            )
def add_provider_packages_to_extras_requirements(extra: str, providers: List[str]) -> None: