Windows: Fix dockerfile\parser unit test

Signed-off-by: John Howard <jhoward@microsoft.com>

rewritten from github.com/moby/moby 864e892e2a310c5b67dfd842e39634dd0d99da73

frontend/dockerfile/parser/parser_test.go

@@ -1,10 +1,12 @@
 package parser
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 )
 
@@ -66,6 +68,11 @@ func TestTestData(t *testing.T) {
 			t.Fatalf("Error reading %s's result file: %v", dir, err)
 		}
 
+		if runtime.GOOS == "windows" {
+			// CRLF --> CR to match Unix behaviour
+			content = bytes.Replace(content, []byte{'\x0d', '\x0a'}, []byte{'\x0a'}, -1)
+		}
+
 		if ast.Dump()+"\n" != string(content) {
 			fmt.Fprintln(os.Stderr, "Result:\n"+ast.Dump())
 			fmt.Fprintln(os.Stderr, "Expected:\n"+string(content))