Incompatible with yarn@4.4.0

Here is a package.json I have in my workspace:

```json
{
"private": true,
…
"scripts": {
"build": "yarn run -TB wireit",
"deploy": "yarn run -TB wireit"
},
"wireit": {
"build": {
"command": "./copy_files.py",
…
},
"deploy": {
"command": "firebase deploy",
"dependencies": [
"build"
]
}
}
}
```

`yarn run deploy` runs fine in that folder with yarn@4.0.1.

In 4.4.0, I get this error:

```
❌ package.json:1:1 Script "deploy" not found in the scripts section of this package.json.
```

It appears to be from [`analyzer.ts`](https://github.com/google/wireit/blob/main/src/analyzer.ts#L452), although the error message doesn't specify _which_ package.json is problematic.