Merge pull request #53631 from dixudx/enforce_cobra_required_flags

Automatic merge from submit-queue. 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>.

update vendor spf13/cobra to enforce required flags

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

spf13/cobra#502 has enforced checking flags that marked as required, an error will be raised if unset.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*:fixes #54855
xref #48400
fixes kubernetes/kubectl#121 

**Special notes for your reviewer**:
/assign @liggitt @eparis 

**Release note**:

```release-note
kubectl now enforces required flags at a more fundamental level
```

pkg/kubectl/cmd/completion.go

@@ -97,7 +97,8 @@ func NewCmdCompletion(out io.Writer, boilerPlate string) *cobra.Command {
 	}
 
 	cmd := &cobra.Command{
-		Use:     "completion SHELL",
+		Use: "completion SHELL",
+		DisableFlagsInUseLine: true,
 		Short:   i18n.T("Output shell completion code for the specified shell (bash or zsh)"),
 		Long:    completion_long,
 		Example: completion_example,