build(deps): bump agentkeepalive from 4.1.4 to 4.2.0 (#733)

Bumps [agentkeepalive](https://github.com/node-modules/agentkeepalive) from 4.1.4 to 4.2.0.
- [Release notes](https://github.com/node-modules/agentkeepalive/releases)
- [Changelog](https://github.com/node-modules/agentkeepalive/blob/master/History.md)
- [Commits](node-modules/agentkeepalive@4.1.4...4.2.0)

---
updated-dependencies:
- dependency-name: agentkeepalive
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>