pnpm conversion should remove extra -- used to pass npm args

[slorber]

Describe the bug

Related issue: facebook/docusaurus#9761

npm run swizzle @docusaurus/theme-classic Footer -- --typescript

This is a valid npm command, although afaik -- isn't required by the newest npm versions, older ones still require it.

Unfortunately, the extra -- is not supported by yarn and pnpm

The yarn conversion already removes the extra -- but not the pnpm one:

To Reproduce

On any docusaurus v3.1.1 (latest version) site:

```bash npm2yarn
npm run swizzle @docusaurus/theme-classic Footer -- --typescript
```

Expected behavior

Convert to:

pnpm run swizzle @docusaurus/theme-classic Footer --typescript

Instead of:

pnpm run swizzle @docusaurus/theme-classic Footer -- --typescript

Package & Environment Details

• Environment: macOS, Node 18, npm 10

[nebrelbug]

Just fixed in npm-to-yarn@2.2.0.