cmount: make tests more reliable on Windows

cmd/mountlib/mounttest/read.go

@@ -5,6 +5,7 @@ import (
 	"io/ioutil"
 	"os"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -31,6 +32,7 @@ func TestReadByByte(t *testing.T) {
 		assert.NoError(t, err)
 	}
 
+	time.Sleep(100 * time.Millisecond) // FIXME wait for Release
 	run.rm(t, "testfile")
 }