Add Cache::flexiable support (#718)

* Adds `Cache::flexible` support

* Enhance composer.json files with suggested package requirements

* Enhance composer.json with additional suggested package for defer function

* 添加 `Cache::flexible` 方法以支持后台刷新过期缓存项

* 在 `Cache` 类中添加对 `flexible` 方法的 PHPStan 忽略注释

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Co-authored-by: Deeka Wong <[email protected]>

Author: huangdijia

composer.json

@@ -38,8 +38,8 @@
         "ramsey/uuid": "^4.7"
     },
     "suggest": {
-        "hyperf/redis": "Required to use Redis client.",
-        "hyperf/signal": "Required to use Signal manager."
+        "hyperf/redis": "Required to use Redis client.(~3.1.0)",
+        "hyperf/signal": "Required to use Signal manager.(~3.1.0)"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,