Automatic merge from submit-queue (batch tested with PRs 58216, 58193, 53033, 58219, 55921). 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>.

Fix golint errors on test/e2e/e2e.go

**What this PR does / why we need it**:

When running golint on test/e2e/e2e.go, the following erros
were faced:

 $ golint e2e.go
 e2e.go:329:2: var metricsJson should be metricsJSON
 e2e.go:342:1: comment on exported function RunE2ETests should be of the form "RunE2ETests ..."

This PR fixes them.

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

`NONE`

**Special notes for your reviewer**:

`NONE`

**Release note**:

`NONE`