build(deps): bump braze-specification from f27970e to 476921d

Bumps [braze-specification](https://github.com/braze-community/braze-specification) from `f27970e` to `476921d`.
- [Release notes](https://github.com/braze-community/braze-specification/releases)
- [Commits](braze-community/braze-specification@f27970e...476921d)

---
updated-dependencies:
- dependency-name: braze-specification
  dependency-type: direct:production
...

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