Update slack-sdk requirement from ==3.30.* to >=3.30,<3.32

Updates the requirements on [slack-sdk](https://github.com/slackapi/python-slack-sdk) to permit the latest version.
- [Release notes](https://github.com/slackapi/python-slack-sdk/releases)
- [Changelog](https://github.com/slackapi/python-slack-sdk/blob/main/docs-v2/changelog.html)
- [Commits](slackapi/python-slack-sdk@v3.30.0...v3.31.0)

---
updated-dependencies:
- dependency-name: slack-sdk
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

setup.py

@@ -22,7 +22,7 @@
         "pyyaml==6.0.*",
         "croniter==2.0.*",
         "tabulate==0.9.*",
-        "slack-sdk==3.30.*",
+        "slack-sdk>=3.30,<3.32",
         "backoff==2.2.*",
     ],
     extras_require={