chore(deps): bump axios from 0.21.1 to 0.21.4 in /tests/dev-server

Bumps [axios](https://github.com/axios/axios) from 0.21.1 to 0.21.4.
- [Release notes](https://github.com/axios/axios/releases)
- [Changelog](https://github.com/axios/axios/blob/v0.21.4/CHANGELOG.md)
- [Commits](axios/axios@v0.21.1...v0.21.4)

---
updated-dependencies:
- dependency-name: axios
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]