Kubeadm: Expose the `kubeadm join` workflow as phases

  - **apiserver_flowcontrol_priority_level_seat_count_watermarks**: histograms of high and low watermarks of number of seats occupied by executing requests (both regular and final-delay phases included), broken down by priority_level.

- kubeadm now includes the ability to specify certificate encryption and decryption keys for the upload and download certificate phases as part of the new v1beta2 kubeadm config format. ([#77012](https://github.com/kubernetes/kubernetes/pull/77012), [@rosti](https://github.com/rosti))

  TF_Operation* plusB = Add(plus2, b, graph, s, "plusB");
  ASSERT_EQ(TF_OK, TF_GetCode(s)) << TF_Message(s);

  // Setup a session and a partial run handle.  The partial run will allow
  // computation of A + 2 + B in two phases (calls to TF_SessionPRun):
  // 1. Feed A and get (A+2)
  // 2. Feed B and get (A+2)+B
  TF_SessionOptions* opts = TF_NewSessionOptions();
  TF_Session* sess = TF_NewSession(graph, opts, s);

- If `kubeadm reset` finds no etcd member ID for the peer it removes during the `remove-etcd-member` phase, it continues immediately to other phases, instead of retrying the phase for up to 3 minutes before continuing. ([#117916](https://github.com/kubernetes/kubernetes/pull/117916), [@dlipovetsky](https://github.com/dlipovetsky)) [SIG Cluster Lifecycle]

	type inference fails.
	</p>
</li>
</ol>

<p>
If not all type arguments have been found after these two phases, type inference fails.
</p>

<p>
If the two phases are successful, type inference determined a type argument for each
bound type parameter:
</p>

<pre>
	P<sub>k</sub> ➞ A<sub>k</sub>
</pre>

<p>

- Kubeadm: switch control-plane static...

- If `kubeadm reset` finds no etcd member ID for the peer it removes during the `remove-etcd-member` phase, it continues immediately to other phases, instead of retrying the phase for up to 3 minutes before continuing. ([#117724](https://github.com/kubernetes/kubernetes/pull/117724), [@dlipovetsky](https://github.com/dlipovetsky)) [SIG Cluster Lifecycle]

endpoint for the kubelet when creating a cluster with "kubeadm init" or when joining control plane nodes with "kubeadm join".  The "kubeadm join" workflow now includes two new experimental phases called "control-plane-join-etcd" and "kubelet-wait-bootstrap" which will be used when the feature gate is enabled. This phases will be marked as non-experimental when ControlPlaneKubeletLocalMode becomes GA. During "kubeadm upgrade" commands, if the feature gate is enabled, modify the "/etc/kubernetes/kubelet.conf...

   ([#123341](https://github.com/kubernetes/kubernetes/pull/123341), [@neolit123](https://github.com/neolit123))