Refactors pkg/testutils

Solves #11579.

Signed-off-by: bobby abbott <ttobbaybbob@gmail.com>

testutils/README.md

@@ -1,2 +0,0 @@
-`testutils` is a collection of utility functions to facilitate the writing
-of tests. It is used in various places by the Docker test suite.

testutils/utils.go

@@ -1,37 +0,0 @@
-package testutils
-
-import (
-	"math/rand"
-	"testing"
-	"time"
-)
-
-const chars = "abcdefghijklmnopqrstuvwxyz" +
-	"ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
-	"~!@#$%^&*()-_+={}[]\\|<,>.?/\"';:` "
-
-// Timeout calls f and waits for 100ms for it to complete.
-// If it doesn't, it causes the tests to fail.
-// t must be a valid testing context.
-func Timeout(t *testing.T, f func()) {
-	onTimeout := time.After(100 * time.Millisecond)
-	onDone := make(chan bool)
-	go func() {
-		f()
-		close(onDone)
-	}()
-	select {
-	case <-onTimeout:
-		t.Fatalf("timeout")
-	case <-onDone:
-	}
-}
-
-// RandomString returns random string of specified length
-func RandomString(length int) string {
-	res := make([]byte, length)
-	for i := 0; i < length; i++ {
-		res[i] = chars[rand.Intn(len(chars))]
-	}
-	return string(res)
-}