fix(plugin-legacy): add invoke to modern detector to avoid terser treeshaking

[donaldyu]

Description

fixdetectModernBrowserDetector in @vite/plugin-legacy.Because terser will remove empty functions that are not being called which will cause detector different between html and entry file.For example:

Additional context

---

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, especially the Pull Request Guidelines.
• 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).
• Update the corresponding documentation if needed.
• Ideally, include relevant tests that fail without this PR but pass with it.

[bluwy]

LGTM. Can you also run

vite/packages/plugin-legacy/README.md

Lines 162 to 164 in 55335cc

	<!--
	Run `node --input-type=module -e "import {cspHashes} from '@vitejs/plugin-legacy'; console.log(cspHashes.map(h => 'sha256-'+h))"` to retrieve the value.
	-->

to update the CSP hashes?

[donaldyu]

done

[Rotzbua]

Changing hash is a breaking(!) change. Should be mentioned in changelog.