func RequireFakeEnvoy(t *testing.T, path string) {
	builtFakeEnvoy.Do(func() {
		fakeEnvoyBin = RequireBuildFakeBinary(t, t.TempDir(), "envoy", fakeEnvoySrc)
	})
	require.NoError(t, os.WriteFile(path, fakeEnvoyBin, 0700))  
}
RequireFakeEnvoy writes fakeEnvoyBin to the given path. This is embedded here because it is reused in many places.
package fakebinary
import (
	_ "embed"  
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"sync"
	"testing"
	"github.com/stretchr/testify/require"
)
var exe = func() string {
	if runtime.GOOS == "windows" {
		return ".exe"
	}
	return ""
}()
var (
	fakeEnvoySrc []byte
	fakeEnvoyBin   []byte
	builtFakeEnvoy sync.Once
)