fix(coverage): prevent reportsDirectory from removing user's project

[AriPerkkio]

Description

Configuration below can remove user's whole project including local Git history from .git. One could accidentally use that when trying to generate coverage reports in the root of project instead of the default ./coverage, and find out that their whole project is now wiped (that's me 🙃).

Details

// Don't run this
export default defineConfig({
  test: {
    coverage: {
      reportsDirectory: './',
    },
  },
})

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