Bump @babel/plugin-proposal-decorators from 7.14.5 to 7.15.4 (#16711)

Bump @babel/plugin-proposal-decorators from 7.14.5 to 7.15.4 (#16711)

Bumps [@babel/plugin-proposal-decorators](https://github.com/babel/babel/tree/HEAD/packages/babel-plugin-proposal-decorators) from 7.14.5 to 7.15.4.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/commits/v7.15.4/packages/babel-plugin-proposal-decorators)

---
updated-dependencies:
- dependency-name: "@babel/plugin-proposal-decorators"
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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