Merge pull request #46946 from kellycampbell/sort-contexts

Automatic merge from submit-queue (batch tested with PRs 46946, 45792). 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>.

kubectl config get-contexts: sort output

This sorts the output of kubectl config get-contexts because the ordering is otherwise non-stable and makes it harder to find the context you're looking for when you have more than a few.

```release-note
The output of kubectl config get-contexts is now sorted alphabetically by the context name.
```

pkg/kubectl/cmd/config/get_contexts.go

@@ -19,6 +19,7 @@ package config
 import (
 	"fmt"
 	"io"
+	"sort"
 	"strings"
 	"text/tabwriter"
 
@@ -138,6 +139,7 @@ func (o GetContextsOptions) RunGetContexts() error {
 		}
 	}
 
+	sort.Strings(toPrint)
 	for _, name := range toPrint {
 		err = printContext(name, config.Contexts[name], out, o.nameOnly, config.CurrentContext == name)
 		if err != nil {