refactor(deps-dev): bump @babel/core from 7.14.6 to 7.15.8

Bumps [@babel/core](https://github.com/babel/babel/tree/HEAD/packages/babel-core) from 7.14.6 to 7.15.8.
- [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/v7.15.8/packages/babel-core)

---
updated-dependencies:
- dependency-name: "@babel/core"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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