*  - AWS_SSH_KEY, previously assumed to be an absolute path can now be either relative or absolute
    *  - LOCAL_SSH_KEY (for local and vsphere providers) was previously assumed to be a filename relative to ~/.ssh but can now also be an absolute path
    *  - KUBE_SSH_KEY (for skeleton provider) was previously assumed to be a filename relative to ~/.ssh but can now also be an absolute path

## Changelog since v1.23.15

## Changes by Kind

### API Change

- Kubernetes 1.23 is now built with go1.19.4. To match behavior of previous Kubernetes 1.23 patch releases:
  - `kube-apiserver` defaults the GOGC setting to 63, to approximate go1.17 garbage collection memory performance in heavily loaded API servers

you migrate to configure patches via `{Init|Join}Configuration.patches.directory`. For the time being, these flags can be mixed with `--config`, but that might change in the future. On a command line, the last *patches flag takes precedence over previous flags and the value in config. `kubeadm upgrade --patches` will continue to be the only available option, since `upgrade` does not support a configuration file yet. ([#103063](https://github.com/kubernetes/kubernetes/pull/103063), [@neolit123](h...

- **Overhauled metrics**: Kubernetes has previously made extensive use of a global metrics registry to register metrics to be exposed. By implementing a metrics registry, metrics are registered in more transparent means. Previously, Kubernetes metrics have been excluded from any kind of stability requirements.

- Fixed a 1.27 scheduling regression that PostFilter plugin may not function if previous PreFilter plugins return Skip ([#119942](https://github.com/kubernetes/kubernetes/pull/119942), [@Huang-Wei](https://github.com/Huang-Wei)) [SIG Scheduling and Testing]

- The API server now detects and fails on startup if there are conflicting issuers between JWT authenticators and service account configurations. Previously, such configurations would run but could be inconsistently effective depending...

   * was GET or HEAD.
   *
   * In OkHttp 4.6 and later, HTTP 307 and 308 redirects are honored for all request methods.
   *
   * If you're upgrading to OkHttp 4.6 and would like to retain the previous behavior, install this
   * as a **network interceptor**. It will strip the `Location` header of impacted responses to
   * prevent the redirect.
   *
   * ```
   * OkHttpClient client = client.newBuilder()

- Added support for specifying `controlplane` or `cluster` egress selectors in JWT authenticators via the `issuer.egressSelectorType` field in the `AuthenticationConfiguration.jwt` array. If unset, the previous behavior of using no egress selector is preserved. This functionality requires the `StructuredAuthenticationConfigurationEgressSelector` beta feature gate (enabled by default). ([#132768](https://github.com/kubernetes/kubernetes/pull/132768), [@...

- Fixed a race condition on API server startup ensuring previously created webhook configurations are effective before the first write request is admitted. ([#95783](https://github.com/kubernetes/kubernetes/pull/95783), [@roycaihw](https://github.com/roycaihw)) [SIG API Machinery]

   * separator between each, to {@code appendable}.
   */
  @CanIgnoreReturnValue
  public <A extends Appendable> A appendTo(A appendable, Iterable<?> parts) throws IOException {
    return appendTo(appendable, parts.iterator());
  }

  /**
   * Appends the string representation of each of {@code parts}, using the previously configured