Revert unnecessary change

Author: hcancelik

Diff for: docs/middleware/cache.md

@@ -52,7 +52,7 @@ app.Use(cache.New(cache.Config{
         return time.Second * time.Duration(newCacheTime)
     },
     KeyGenerator: func(c fiber.Ctx) string {
-  return utils.CopyString(c.Path())
+		return utils.CopyString(c.Path())
     },
 }))