feat 修改usn类型为string

internal/grpc_server/server/a_test.go

@@ -0,0 +1,11 @@
+package server
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestName(t *testing.T) {
+
+	t.Logf("step: %v", fmt.Sprintf("aa %v bb", []string{"1", "2"}))
+}