Swift: Bump the swift-dependencies group with 2 updates

Bumps the swift-dependencies group with 2 updates: [github.com/apple/swift-metrics](https://github.com/apple/swift-metrics) and [github.com/apple/swift-nio-transport-services](https://github.com/apple/swift-nio-transport-services).


Updates `github.com/apple/swift-metrics` from 2.4.1 to 2.4.2
- [Release notes](https://github.com/apple/swift-metrics/releases)
- [Commits](apple/swift-metrics@2.4.1...2.4.2)

Updates `github.com/apple/swift-nio-transport-services` from 1.20.1 to 1.21.0
- [Release notes](https://github.com/apple/swift-nio-transport-services/releases)
- [Commits](apple/swift-nio-transport-services@1.20.1...1.21.0)

---
updated-dependencies:
- dependency-name: github.com/apple/swift-metrics
  dependency-type: indirect
  update-type: version-update:semver-patch
  dependency-group: swift-dependencies
- dependency-name: github.com/apple/swift-nio-transport-services
  dependency-type: indirect
  update-type: version-update:semver-minor
  dependency-group: swift-dependencies
...

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

Author: dependabot[bot]