rector: apply some php-73/php-80 rules (#4682)

* rector: apply php8 string rules

- `StrEndsWithRector`
- `StrStartsWithRector`
- `StrContainsRector`

* PhpStan fixes

Author: Sven Reichel

.phpstan.dist.baseline.neon

@@ -3888,12 +3888,6 @@ parameters:
 			count: 2
 			path: app/code/core/Mage/Directory/Model/Observer.php
 
-		-
-			message: '#^Left side of && is always true\.$#'
-			identifier: booleanAnd.leftAlwaysTrue
-			count: 1
-			path: app/code/core/Mage/Downloadable/Block/Catalog/Product/Links.php
-
 		-
 			message: '#^Cannot call method streamRead\(\) on resource\.$#'
 			identifier: method.nonObject

.rector.php

@@ -16,6 +16,9 @@
 
 try {
     return RectorConfig::configure()
+        ->withPhpSets(
+            php55: true,
+        )
         ->withPaths([
             __DIR__,
         ])
@@ -32,9 +35,6 @@
             Php80\Class_\ClassPropertyAssignToConstructorPromotionRector::class,
             Php80\Class_\StringableForToStringRector::class,
             Php80\FunctionLike\MixedTypeRector::class,
-            Php80\Identical\StrEndsWithRector::class,
-            Php80\Identical\StrStartsWithRector::class,
-            Php80\NotIdentical\StrContainsRector::class,
             TypeDeclaration\ClassMethod\ReturnNeverTypeRector::class,
             __DIR__ . '/shell/translations.php',
             __DIR__ . '/shell/update-copyright.php',