fix: fix log.Helper.WithContext msg key missing (#1571)

log/helper.go

@@ -39,6 +39,7 @@ func NewHelper(logger Logger, opts ...Option) *Helper {
 // to ctx. The provided ctx must be non-nil.
 func (h *Helper) WithContext(ctx context.Context) *Helper {
 	return &Helper{
+		msgKey: h.msgKey,
 		logger: WithContext(ctx, h.logger),
 	}
 }