Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

Replace hard-code "cpu" and "memory" to consts

**What this PR does / why we need it**:
There are many places using hard coded "cpu" and "memory" as resource name. This PR replace them to consts.

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

**Special notes for your reviewer**:
/kind cleanup

**Release note**:

```release-note
NONE
```