[ci:component:github.com/gardener/machine-controller-manager:v0.49.1->v0.51.1]

[gardener-robot-ci-1]

Release Notes:

New metrics introduced: 
- api_request_duration_seconds -> tracks time taken for successful invocation of provider APIs. This metric can be filtered by provider and service.
- driver_request_duration_seconds -> tracks total time taken to successfully complete driver method invocation. This metric can be filtered by provider and operation.
- driver_requests_failed_total -> records total number of failed driver API requests. This metric can be filtered by provider, operations and error_code.

A new make target is introduced to add license headers.

Removed dead metrics code and refactored the remaining metrics code

Added `errorCode` field in the `LastOperation` struct. This should be implemented only for the `CreateMachine` call in the `triggerCreationFlow`. This field will be utilized by Cluster autoscaler to do early backoff 

Included `UnavailableReplicas` in determining if a machine deployment status update is needed

The default `machine-safety-orphan-vms-period` has been reduced from 30m to 15m.

Change OCI Image Registry from GCR (`eu.gcr.io/gardener-project`) to Artifact-Registry (`europe-docker.pkg.dev/gardener-project/releases`). Users should update their references.

fixed IT for seed with k8s >= 1.27 as control cluster 

Fix for edge case of Node object deletion missed during machine termination.

machine controller won't reconcile machine on non-spec update events

Force drain and delete volume attachments for nodes un-healthy due to `ReadOnlyFileSystem` and `NotReady` for too long

Added a new metric that will allow to get the number of stale (due to unhealthiness) machines  that are getting terminated

Phase transition diagram for a machine object is added to FAQs

MCM restart happens properly in integration tests now. This fix will get activated, once this version is vendored in your mcm-provider

Bump `k8s.io/*` deps to `v0.28.2`

An edge case where outdated DesiredReplicas annotation blocked a rolling update is fixed.

Updated to go v1.20.5

Makefile targets have changed: Introduced gardener-setup, gardener-restore, gardener-local-mcm-up, non-gardener-setup, non-gardener-restore,  non-gardener-local-mcm-up. Users can also directly use the scripts which are used by these makefile targets.

Bump `k8s.io/*` deps to v0.27.2

status.Status now captures underline cause, allowing consumers to introspect the error returned by the provider. WrapError() function could be used to wrap the provider error

Removes `node.machine.sapcloud.io/not-managed-by-mcm` annotation from nodes managed by the MCM.

[gardener-robot]

@gardener-robot-ci-1 Thank you for your contribution.

[rishabh-11]

/lgtm