2 tests for yarn doesn't pass on windows `by default`

### Describe the bug If somebody(like me) doesn't have `yarn` installed globally. For `packages/wxt` those 2 tests doesn't pass: <img width="1137" height="522" alt="Image" src="https://github.com/user-attachments/assets/0c1336be-a9f3-41b6-a30e-fd22570508a8" /> To fix it, i need to install yarn globally (Only sad reaction) To make better DX, we can place `yarn` as a `devDeps` inside this package. But the big problem is: <img width="667" height="99" alt="Image" src="https://github.com/user-attachments/assets/77fbef4b-ffee-410e-92d8-99bbd10ed9c0" /> And it seems not supported anymore: Latest version have over 2 years: https://www.npmjs.com/package/yarn There's no move in repo: https://github.com/yarnpkg/yarn/commits/master/ I think good idea is to get rid of this package and those tests. PS: OKK yarn drops support for version 1 and changed repo: https://github.com/yarnpkg/berry/releases IT'S `berry` right now??? ### Used Package Manager yarn ### Validations - [x] Read the [Contributing Guidelines](https://github.com/wxt-dev/wxt/blob/main/CONTRIBUTING.md). - [x] Read the [docs](https://wxt.dev/guide/installation.html). - [x] Check that there isn't [already an issue](https://github.com/wxt-dev/wxt/issues) 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](https://github.com/wxt-dev/wxt/discussions) or join our [Discord Chat Server](https://discord.gg/ZFsZqGery9). - [x] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.