build(deps): bump slackclient from 2.9.3 to 2.9.4 in /tools/base (#20947)
build(deps): bump slackclient from 2.9.3 to 2.9.4 in /tools/base (#20947)

Bumps [slackclient](https://github.com/slackapi/python-slack-sdk) from 2.9.3 to 2.9.4.
- [Release notes](https://github.com/slackapi/python-slack-sdk/releases)
- [Commits](https://github.com/slackapi/python-slack-sdk/compare/v2.9.3...v2.9.4)

---
updated-dependencies:
- dependency-name: slackclient
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
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