security(deps): bump axios and @slack/bolt

Bumps [axios](https://github.com/axios/axios) to 1.6.0 and updates ancestor dependency [@slack/bolt](https://github.com/slackapi/bolt). These dependencies need to be updated together.


Updates `axios` from 0.27.2 to 1.6.0
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/v1.x/CHANGELOG.md)
- [Commits](axios/axios@v0.27.2...v1.6.0)

Updates `@slack/bolt` from 3.13.3 to 3.15.0
- [Release notes](https://github.com/slackapi/bolt/releases)
- [Commits](https://github.com/slackapi/bolt/compare/@slack/bolt@3.13.3...@slack/bolt@3.15.0)

---
updated-dependencies:
- dependency-name: axios
  dependency-type: indirect
- dependency-name: "@slack/bolt"
  dependency-type: direct:development
...

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