Bump msw from 1.3.5 to 2.6.9 in /webapp

Bumps [msw](https://github.com/mswjs/msw) from 1.3.5 to 2.6.9.
- [Release notes](https://github.com/mswjs/msw/releases)
- [Changelog](https://github.com/mswjs/msw/blob/main/CHANGELOG.md)
- [Commits](mswjs/msw@v1.3.5...v2.6.9)

---
updated-dependencies:
- dependency-name: msw
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>