Merge pull request #32106 from jellonek/fd_leaks

Automatic merge from submit-queue

Ensure that we are closing files.

**What this PR does / why we need it**: In several places we are leaking file descriptors. This could be problematic on systems with low ulimits for them.

**Release note**:
```release-note
```

test/e2e/kubectl.go

@@ -1529,6 +1529,7 @@ func readBytesFromFile(filename string) []byte {
 		framework.Failf(err.Error())
 	}
 	defer file.Close()
+
 	data, err := ioutil.ReadAll(file)
 	if err != nil {
 		framework.Failf(err.Error())