scalability testing in a continuous integration (CI) environment. The SIG
defined a concrete process for scalability testing, created
documentation for the current scalability thresholds, and defined a new set of
Service Level Indicators (SLIs) and Service Level Objectives (SLOs) for the system.
Here's the release [scalability validation report].

[SIG Scalability]: https://github.com/kubernetes/community/tree/master/sig-scalability

// https://www.iana.org/domains/root/db/tunes.html
tunes

// tushu : Amazon Registry Services, Inc.
// https://www.iana.org/domains/root/db/tushu.html
tushu

// tvs : T V SUNDRAM IYENGAR  & SONS LIMITED
// https://www.iana.org/domains/root/db/tvs.html
tvs

// ubank : National Australia Bank Limited
// https://www.iana.org/domains/root/db/ubank.html
ubank

// ubs : UBS AG

- Kubeadm: fix panic when no UpgradeConfiguration was found in the config file ([#130312](https://github.com/kubernetes/kubernetes/pull/130312), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]
- Makes kubelet's /metrics/slis endpoint always available ([#130084](https://github.com/kubernetes/kubernetes/pull/130084), [@richabanker](https://github.com/richabanker)) [SIG Architecture, Instrumentation and Node]

## Changelog since v1.28.6

## Changes by Kind

### Feature

- Add process_start_time_seconds to /metrics/slis endpoint of all components ([#122750](https://github.com/kubernetes/kubernetes/pull/122750), [@richabanker](https://github.com/richabanker)) [SIG Architecture, Instrumentation and Testing]
- Kubernetes is now built with go 1.21.7

Marchesi, Max Melnick, Micael Carvalho, @mikowals, Mostafa Gazar, Nico Galoppo,
Nishant Agrawal, Petr Janda, Yuncheng Li, @raix852, Robert Rose,
@Robin-des-Bois, Rohit Girdhar, Sam Abrahams, satok16, Sergey Kishchenko, Sharkd
Tu, @shotat, Siddharth Agrawal, Simon Denel, @sono-bfio, SunYeop Lee, Thijs
Vogels, @tobegit3hub, @Undo1, Wang Yang, Wenjian Huang, Yaroslav Bulatov, Yuan