Bump @vitest/coverage-istanbul from 1.4.0 to 1.6.0

Bumps [@vitest/coverage-istanbul](https://github.com/vitest-dev/vitest/tree/HEAD/packages/coverage-istanbul) from 1.4.0 to 1.6.0.
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v1.6.0/packages/coverage-istanbul)

---
updated-dependencies:
- dependency-name: "@vitest/coverage-istanbul"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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