Drop Support for EOL Python 3.6, 3.7 and 3.8

As of today per Python Software Foundation policy here: https://devguide.python.org/versions/

• Python 3.6 has ended security support and it's end of life was - 2021-12-23. It's 3 years unsupported!
• Python 3.7 has ended security support and it's end of life was - 2023-06-27. It's 1.5 years unsupported!
• Python 3.8 has ended security support and it's end of life was - 2024-10-07. It's 3 months unsupported!

Does Slack SDK plans to remove support for those Python versions? Promoting unsupported version of Python has security concerns and it shouldn't be promoted.

I've realised this while working on #1633 as I wasn't expecting that Python 3.6 is in use and I was using features that were added in Python 3.8 so I lived under assumption that I can use everything from 3.9 and above.

Category

• slack_sdk.web.WebClient (sync/async) (Web API client)
• slack_sdk.webhook.WebhookClient (sync/async) (Incoming Webhook, response_url sender)
• slack_sdk.models (UI component builders)
• slack_sdk.oauth (OAuth Flow Utilities)
• slack_sdk.socket_mode (Socket Mode client)
• slack_sdk.audit_logs (Audit Logs API client)
• slack_sdk.scim (SCIM API client)
• slack_sdk.rtm (RTM client)
• slack_sdk.signature (Request Signature Verifier)

Requirements

Please read the Contributing guidelines and Code of Conduct before creating this issue or pull request. By submitting, you are agreeing to those rules.

ファイル、テスト、エントリポイントは指定されていません。まずプロジェクト設定と、サポート対象の Python バージョンに関する CI の参照を確認し、次に一覧にある SDK コンポーネントを調べて、バージョン固有のサポートを確認してください。完了条件は、これらのコンポーネント全体で Python 3.6、3.7、3.8 が一貫してサポート対象外となり、関連する検証が更新されていることです。