Bump path-to-regexp from 8.2.0 to 8.4.0 in /test/mcp (#305927)

Bumps [path-to-regexp](https://github.com/pillarjs/path-to-regexp) from 8.2.0 to 8.4.0.
- [Release notes](https://github.com/pillarjs/path-to-regexp/releases)
- [Changelog](https://github.com/pillarjs/path-to-regexp/blob/master/History.md)
- [Commits](https://github.com/pillarjs/path-to-regexp/compare/v8.2.0...v8.4.0)

---
updated-dependencies:
- dependency-name: path-to-regexp
  dependency-version: 8.4.0
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Raymond Zhao <[email protected]>