Bump cipher-base from 1.0.4 to 1.0.6 in /polling-app-client

Bumps [cipher-base](https://github.com/crypto-browserify/cipher-base) from 1.0.4 to 1.0.6.
- [Changelog](https://github.com/browserify/cipher-base/blob/master/CHANGELOG.md)
- [Commits](browserify/cipher-base@v1.0.4...v1.0.6)

---
updated-dependencies:
- dependency-name: cipher-base
  dependency-version: 1.0.6
  dependency-type: indirect
...

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Author: dependabot[bot]