refactor: remove ?used inject in glob plugin

[sapphi-red]

Description

This code was added by antfu/vite-plugin-glob@00a82b7.
But it is not needed because ?used is injected by import-analysis which runs at the end.

Additional context

To fix_ #8245, import-analysis-build needs to resolve id before deciding to inject ?used.
This PR is needed to dedupe that logic.

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[netlify]

✅ Deploy Preview for vite-docs-main canceled.

Name	Link
🔨 Latest commit	62d773a
🔍 Latest deploy log	https://app.netlify.com/sites/vite-docs-main/deploys/62c1c2e54d35e50009b5eeec