Bump https-proxy-agent from 2.2.1 to 2.2.4 in /test/end-to-end-tests
Bumps [https-proxy-agent](https://github.com/TooTallNate/node-https-proxy-agent) from 2.2.1 to 2.2.4.
- [Release notes](https://github.com/TooTallNate/node-https-proxy-agent/releases)
- [Commits](https://github.com/TooTallNate/node-https-proxy-agent/compare/2.2.1...2.2.4)
Signed-off-by: dependabot[bot] <support@github.com>