Automatic merge from submit-queue (batch tested with PRs 54042, 54185, 54880). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

refactor ReplicaSet sync call tree

**What this PR does / why we need it**:
This PR refactors ReplicaSet sync call tree by refactoring `manageReplicas` and `syncReplicaSet` functions into smaller functions, and adding unit tests to each of the smaller functions.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: xref #52118

**Release note**:

```release-note
NONE
```
**TODO**:
- `manageReplicas`
  - [x] move both outer and inner `batchSize` loops to a helper function named `slowStartBatch`, and test the function
  - [x] add a helper function returning a list named `podsToDelete`, test the function, and refactor `DeletePod` loop to use the list
  - [x] refactor skipped pod handling such that it happens after `slowStartBatch` returns

- `syncReplicaSet`
  - [x] add unit tests for `calculateStatus`
  - [x] move `canAdoptFunc` to a helper function