Coverage report creates html report by default

[daribock]

Describe the bug

If you don't define anything for --coverage in the vite.config.js there will always be a html report in the coverage folder. If this is meant to be like this it would be nice if you could add this in the docs. 😊

Reproduction

Install vitest and use coverage option to create coverage report.

vitest run --coverage

System Info

System:
    OS: macOS 12.5.1
    CPU: (12) x64 Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
    Memory: 24.99 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 16.17.0
    npm: 8.19.2
  Browsers:
    Chrome: 105.0.5195.125
    Edge: 105.0.1343.33
    Safari: 15.6.1
  npmPackages:
    @vitejs/plugin-react: ^2.0.1 => 2.1.0
    vite: ^3.0.7 => 3.1.0
    vitest: ^0.23.2 => 0.23.2

Used Package Manager

pnpm

Validations

• [X] Follow our Code of Conduct
• [X] Read the Contributing Guidelines.
• [X] Read the docs.
• [X] Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• [X] Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• [X] The provided reproduction is a minimal reproducible example of the bug.