Fix golint for pkg/probe

This change adds comments to exported things and renames the tcp,
http, and exec probe interfaces to just be Prober within their
namespace.

Issue #68026

pkg/probe/exec/exec.go

@@ -23,16 +23,21 @@ import (
 	"github.com/golang/glog"
 )
 
-func New() ExecProber {
+// New creates a Prober.
+func New() Prober {
 	return execProber{}
 }
 
-type ExecProber interface {
+// Prober is an interface defining the Probe object for container readiness/liveness checks.
+type Prober interface {
 	Probe(e exec.Cmd) (probe.Result, string, error)
 }
 
 type execProber struct{}
 
+// Probe executes a command to check the liveness/readiness of container
+// from executing a command. Returns the Result status, command output, and
+// errors if any.
 func (pr execProber) Probe(e exec.Cmd) (probe.Result, string, error) {
 	data, err := e.CombinedOutput()
 	glog.V(4).Infof("Exec probe response: %q", string(data))
@@ -41,9 +46,8 @@ func (pr execProber) Probe(e exec.Cmd) (probe.Result, string, error) {
 		if ok {
 			if exit.ExitStatus() == 0 {
 				return probe.Success, string(data), nil
-			} else {
-				return probe.Failure, string(data), nil
 			}
+			return probe.Failure, string(data), nil
 		}
 		return probe.Unknown, "", err
 	}