v3.30.0

Changes

• feat: add team.externalTeams.list by @WilliamBergamin in https://github.com/slackapi/python-slack-sdk/pull/1512
• chore: align README pattern by @WilliamBergamin in https://github.com/slackapi/python-slack-sdk/pull/1513
• chore(release): 3.30.0 by @WilliamBergamin in https://github.com/slackapi/python-slack-sdk/pull/1514

All issues/pull requests: https://github.com/slackapi/python-slack-sdk/milestone/99?closed=1 Full Changelog: https://github.com/slackapi/python-slack-sdk/compare/v3.29.0...v3.30.0