2.13.5

Created by: nicksnyder

waiting on https://buildkite.com/sourcegraph/sourcegraph/builds/23815

TODO (post merge)

• notify https://github.com/sourcegraph/sourcegraph/issues/968
• update changelog on about
• release cluster version https://github.com/sourcegraph/sourcegraph/issues/1043
• update latestReleaseKubernetesBuild