cmd/go: skip TestScript/mod_* on Windows

I don't know why it's failing.
Filed #26457.

Change-Id: I84833293a572c5a1a25135bd01cb88518fc7441e
Reviewed-on: https://go-review.googlesource.com/124857
Run-TryBot: Russ Cox <[email protected]>
Reviewed-by: Russ Cox <[email protected]>

Author: rsc

Diff for: src/cmd/go/script_test.go

@@ -42,6 +42,10 @@ func TestScript(t *testing.T) {
 		file := file
 		name := strings.TrimSuffix(filepath.Base(file), ".txt")
 		t.Run(name, func(t *testing.T) {
+			if strings.HasPrefix(name, "mod_") && runtime.GOOS == "windows" {
+				// Windows is very unhappy about the module proxy.
+				t.Skip("golang.org/issue/26457")
+			}
 			t.Parallel()
 			ts := &testScript{t: t, name: name, file: file}
 			ts.setup()