PHP 8.2 | Squiz/ClassDeclaration: allow for readonly classes

Includes unit test.

Ref:
* https://wiki.php.net/rfc/readonly_classes

src/Standards/Squiz/Sniffs/Classes/ClassDeclarationSniff.php

@@ -65,6 +65,7 @@ public function processOpen(File $phpcsFile, $stackPtr)
 
                 if ($tokens[($stackPtr - 2)]['code'] !== T_ABSTRACT
                     && $tokens[($stackPtr - 2)]['code'] !== T_FINAL
+                    && $tokens[($stackPtr - 2)]['code'] !== T_READONLY
                 ) {
                     if ($spaces !== 0) {
                         $type  = strtolower($tokens[$stackPtr]['content']);

src/Standards/Squiz/Tests/Classes/ClassDeclarationUnitTest.inc

@@ -119,3 +119,12 @@ class IncorrectCodeBeforeClosingBrace
 {
 
 echo phpinfo();}
+
+readonly
+class Test
+{
+}
+
+readonly    class Test
+{
+}

src/Standards/Squiz/Tests/Classes/ClassDeclarationUnitTest.inc.fixed

@@ -130,3 +130,11 @@ class IncorrectCodeBeforeClosingBrace
 
 echo phpinfo();
 }
+
+readonly class Test
+{
+}
+
+readonly class Test
+{
+}

src/Standards/Squiz/Tests/Classes/ClassDeclarationUnitTest.php

@@ -61,6 +61,8 @@ public function getErrorList()
             116 => 1,
             118 => 1,
             121 => 1,
+            124 => 2,
+            128 => 2,
         ];
 
     }//end getErrorList()