Bump k8s.io/uitls to 8e7ff06

The reason for the bump is the new functionality of the
k8s.io/utils/exec package which allows
- to get a hold of the process' std{out,err} as `io.Reader`s
- to `Start` a process and `Wait` for it

This should help on addressing #70890 by allowing to wrap std{out,err}
of the process to be wrapped with a `io.limitedReader`.

It also updates
- k8s.io/kubernetes/pkg/probe/exec.FakeCmd
- k8s.io/kubernetes/pkg/kubelet/prober.execInContainer
- k8s.io/kubernetes/cmd/kubeadm/app/phases/kubelet.fakeCmd
to implement the changed interface.

The dependency on 'k8s.io/utils/pointer' to the new version has also
been bumped in some staging repos:
- apiserver
- kube-controller-manager
- kube-scheduler

vendor/k8s.io/utils/exec/exec.go

@@ -60,6 +60,17 @@ type Cmd interface {
 	SetStdin(in io.Reader)
 	SetStdout(out io.Writer)
 	SetStderr(out io.Writer)
+	SetEnv(env []string)
+
+	// StdoutPipe and StderrPipe for getting the process' Stdout and Stderr as
+	// Readers
+	StdoutPipe() (io.ReadCloser, error)
+	StderrPipe() (io.ReadCloser, error)
+
+	// Start and Wait are for running a process non-blocking
+	Start() error
+	Wait() error
+
 	// Stops the command by sending SIGTERM. It is not guaranteed the
 	// process will stop before this function returns. If the process is not
 	// responding, an internal timer function will send a SIGKILL to force
@@ -121,6 +132,30 @@ func (cmd *cmdWrapper) SetStderr(out io.Writer) {
 	cmd.Stderr = out
 }
 
+func (cmd *cmdWrapper) SetEnv(env []string) {
+	cmd.Env = env
+}
+
+func (cmd *cmdWrapper) StdoutPipe() (io.ReadCloser, error) {
+	r, err := (*osexec.Cmd)(cmd).StdoutPipe()
+	return r, handleError(err)
+}
+
+func (cmd *cmdWrapper) StderrPipe() (io.ReadCloser, error) {
+	r, err := (*osexec.Cmd)(cmd).StderrPipe()
+	return r, handleError(err)
+}
+
+func (cmd *cmdWrapper) Start() error {
+	err := (*osexec.Cmd)(cmd).Start()
+	return handleError(err)
+}
+
+func (cmd *cmdWrapper) Wait() error {
+	err := (*osexec.Cmd)(cmd).Wait()
+	return handleError(err)
+}
+
 // Run is part of the Cmd interface.
 func (cmd *cmdWrapper) Run() error {
 	err := (*osexec.Cmd)(cmd).Run()
@@ -206,10 +241,12 @@ func (e CodeExitError) String() string {
 	return e.Err.Error()
 }
 
+// Exited is to check if the process has finished
 func (e CodeExitError) Exited() bool {
 	return true
 }
 
+// ExitStatus is for checking the error code
 func (e CodeExitError) ExitStatus() int {
 	return e.Code
 }