The incorrect loop logic might lead to a plugin being loaded multiple times, consequently preventing any Pod from being scheduled, which is unexpected. ([#122370](https://github.com/kubernetes/kubernetes/pull/122370), [@caohe](https://github.com/caohe)) [SIG Scheduling]

### Other (Cleanup or Flake)

* The following deprecated flags were removed from `kube-controller-manager`:

  * `replication-controller-lookup-cache-size`
  * `replicaset-lookup-cache-size`
  * `daemonset-lookup-cache-size`

  Don't use these flags. Using deprecated flags causes the server to print a warning. Using a removed flag causes the server to abort the startup.

- Client-go now exposes two new metrics to monitor the client-go logic that
  generate http.Transports for the clients.
  
  - `rest_client_transport_cache_entries` is a gauge metric
  with the number of existing entries in the internal cache
  
  - `rest_client_transport_create_calls_total` is a counter
  that increments each time a new transport is created, storing

   ([#122571](https://github.com/kubernetes/kubernetes/pull/122571), [@p0lyn0mial](https://github.com/p0lyn0mial))
- Added the `apiserver_watch_cache_read_wait` metric to measure the watch cache impact on request latency.
   ([#123190](https://github.com/kubernetes/kubernetes/pull/123190), [@padlar](https://github.com/padlar))

- Added `apiserver_envelope_encryption_dek_cache_filled` to measure number of records in data encryption key (DEK) cache. ([#119878](https://github.com/kubernetes/kubernetes/pull/119878), [@ritazh](https://github.com/ritazh))

  - go_memory_classes_heap_objects_bytes
  - go_memory_classes_heap_released_bytes
  - go_memory_classes_heap_stacks_bytes
  - go_memory_classes_heap_unused_bytes
  - go_memory_classes_metadata_mcache_free_bytes
  - go_memory_classes_metadata_mcache_inuse_bytes
  - go_memory_classes_metadata_mspan_free_bytes
  - go_memory_classes_metadata_mspan_inuse_bytes
  - go_memory_classes_metadata_other_bytes
  - go_memory_classes_os_stacks_bytes