revert random change (#3292)

cmd/frps/main.go

@@ -15,6 +15,9 @@
 package main
 
 import (
+	"math/rand"
+	"time"
+
 	"github.com/fatedier/golib/crypto"
 
 	_ "github.com/fatedier/frp/assets/frps"
@@ -23,6 +26,8 @@ import (
 
 func main() {
 	crypto.DefaultSalt = "frp"
+	// TODO: remove this when we drop support for go1.19
+	rand.Seed(time.Now().UnixNano())
 
 	Execute()
 }