改进缓存类tag方法

library/think/App.php

@@ -20,7 +20,7 @@ use think\route\Dispatch;
  */
 class App extends Container
 {
-    const VERSION = '5.1.36 LTS';
+    const VERSION = '5.1.37 LTS';
 
     /**
      * 当前模块路径

library/think/cache/Driver.php

@@ -249,7 +249,6 @@ abstract class Driver
     {
         if ($this->tag) {
             $key       = $this->getTagkey($this->tag);
-            $prev      = $this->tag;
             $this->tag = null;
 
             if ($this->has($key)) {
@@ -266,7 +265,6 @@ abstract class Driver
             }
 
             $this->set($key, $value, 0);
-            $this->tag = $prev;
         }
     }