AC-6049: Filtering inputs handler in page_cache/block controller

	 * code cleanup

Author: rizwankhgl

app/code/Magento/PageCache/Controller/Block.php

@@ -42,14 +42,14 @@ abstract class Block extends \Magento\Framework\App\Action\Action
     private $layoutCacheKeyName = 'mage_pagecache';
 
     /**
-     * @var RegexFactory
+     * @var private RegexFactory
      */
     private $regexValidatorFactory;
 
     /**
      * Validation pattern for handles array
      */
-    public const VALIDATION_RULE_PATTERN = '/^[a-z]+[a-z0-9_]*$/i';
+    private const VALIDATION_RULE_PATTERN = '/^[a-z]+[a-z0-9_]*$/i';
 
     /**
      * @param \Magento\Framework\App\Action\Context $context

app/code/Magento/PageCache/Test/Unit/Controller/Block/EsiTest.php

@@ -66,6 +66,11 @@ class EsiTest extends TestCase
      */
     protected $translateInline;
 
+    /**
+     * Validation pattern for handles array
+     */
+    private const VALIDATION_RULE_PATTERN = '/^[a-z]+[a-z0-9_]*$/i';
+
     /**
      * Set up before test
      */
@@ -105,7 +110,7 @@ protected function setUp(): void
             ->setMethods(['create'])
             ->getMock();
 
-        $regexObject = new Regex('/^[a-z]+[a-z0-9_]*$/i');
+        $regexObject = new Regex(self::VALIDATION_RULE_PATTERN);
 
         $regexFactoryMock->expects($this->any())->method('create')
             ->willReturn($regexObject);

app/code/Magento/PageCache/Test/Unit/Controller/Block/RenderTest.php

@@ -71,6 +71,11 @@ class RenderTest extends TestCase
      */
     protected $layoutCacheKeyMock;
 
+    /**
+     * Validation pattern for handles array
+     */
+    private const VALIDATION_RULE_PATTERN = '/^[a-z]+[a-z0-9_]*$/i';
+
     /**
      * @inheritDoc
      */
@@ -118,7 +123,7 @@ protected function setUp(): void
             ->setMethods(['create'])
             ->getMock();
 
-        $regexObject = new Regex('/^[a-z]+[a-z0-9_]*$/i');
+        $regexObject = new Regex(self::VALIDATION_RULE_PATTERN);
 
         $regexFactoryMock->expects($this->any())->method('create')
             ->willReturn($regexObject);