Bump netty.version from 4.2.10.Final to 4.2.12.Final (#2605)

Bumps `netty.version` from 4.2.10.Final to 4.2.12.Final.

Updates `io.netty:netty-codec-http` from 4.2.10.Final to 4.2.12.Final
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](https://github.com/netty/netty/compare/netty-4.2.10.Final...netty-4.2.12.Final)

Updates `io.netty:netty-handler` from 4.2.10.Final to 4.2.12.Final
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](https://github.com/netty/netty/compare/netty-4.2.10.Final...netty-4.2.12.Final)

Updates `io.netty:netty-handler-proxy` from 4.2.10.Final to 4.2.12.Final
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](https://github.com/netty/netty/compare/netty-4.2.10.Final...netty-4.2.12.Final)

Updates `io.netty:netty-transport-native-epoll` from 4.2.10.Final to 4.2.12.Final
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](https://github.com/netty/netty/compare/netty-4.2.10.Final...netty-4.2.12.Final)

Updates `io.netty:netty-transport-native-kqueue` from 4.2.10.Final to 4.2.12.Final
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](https://github.com/netty/netty/compare/netty-4.2.10.Final...netty-4.2.12.Final)

---
updated-dependencies:
- dependency-name: io.netty:netty-codec-http
  dependency-version: 4.2.12.Final
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: io.netty:netty-handler
  dependency-version: 4.2.12.Final
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: io.netty:netty-handler-proxy
  dependency-version: 4.2.12.Final
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: io.netty:netty-transport-native-epoll
  dependency-version: 4.2.12.Final
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: io.netty:netty-transport-native-kqueue
  dependency-version: 4.2.12.Final
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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