test: use T.TempDir to create temporary test directory

The directory created by `T.TempDir` is automatically removed when the
test and all its subtests complete.

Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

pkg/cri/server/helpers_linux_test.go

@@ -65,15 +65,9 @@ func TestEnsureRemoveAllWithMount(t *testing.T) {
 		t.Skip("skipping test that requires root")
 	}
 
-	dir1, err := os.MkdirTemp("", "test-ensure-removeall-with-dir1")
-	if err != nil {
-		t.Fatal(err)
-	}
-	dir2, err := os.MkdirTemp("", "test-ensure-removeall-with-dir2")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir2)
+	var err error
+	dir1 := t.TempDir()
+	dir2 := t.TempDir()
 
 	bindDir := filepath.Join(dir1, "bind")
 	if err := os.MkdirAll(bindDir, 0755); err != nil {