composer(deps-dev): update rector/rector requirement from ^2.4 to ^2.6

[dependabot]

Updates the requirements on rector/rector to permit the latest version.

Release notes

Sourced from rector/rector's releases.

Released Rector 2.6.1

Bugfix 🐛

• [composer-based] Fix fatal error in the composer-based command on a lazy-initialized property, e.g. PHPStan UnionType::$normalized (#8280)

PHP Fatal error:  Uncaught Error: Typed property PHPStan\Type\UnionType::$normalized
must not be accessed before initialization in src/Console/Command/ComposerBasedCommand.php:205

---

Composer-based sets keep growing: Twig, nette/utils and the rest of Symfony 📦

Follow-up release to 2.6.0. The composer-based rollout continues - Twig and nette/utils join, and every remaining Symfony rule now declares the package version its target API was added in.

use Rector\Config\RectorConfig;
return RectorConfig::configure()
->withComposerBased(
doctrine: true,
netteUtils: true,
phpunit: true,
symfony: true,
twig: true,
);

The new Twig composer-based set replaces the twig112 → twig127 → ... → twig30 chain with a single set, where every rule checks the installed twig/twig version:

 final class SomeTwigUse
 {
-    public function run(Twig_Environment $twigEnvironment)
+    public function run(\Twig\Environment $twigEnvironment)
     {
-        return new Twig_SimpleFilter('some_filter', 'strlen');
+        return new \Twig\TwigFilter('some_filter', 'strlen');
     }
 }

Package bonding (composer-based rollout) 📦

• [NetteUtils] Bind nette/utils rules to the installed package version; nette-utils4.php becomes composer-based.php and is loaded as a single set (#8275)

... (truncated)

Commits

• b8e68f0 Rector 2.6.1
• 8d4664e Updated Rector to commit 16be33c1c2364d51038752a299fce01043d42576
• 834ed36 Updated Rector to commit 4e11a4088c0634076742b71dc9db4cfbeab4a207
• 77f9eec Updated Rector to commit 4e11a4088c0634076742b71dc9db4cfbeab4a207
• 55176b4 Updated Rector to commit 4e11a4088c0634076742b71dc9db4cfbeab4a207
• c529f35 Updated Rector to commit 72f8056755dc28dd1a8ab8f39900259f129ebae8
• 080ed0f Updated Rector to commit 72f8056755dc28dd1a8ab8f39900259f129ebae8
• 30c1e33 Updated Rector to commit 72f8056755dc28dd1a8ab8f39900259f129ebae8
• 8e262e1 Updated Rector to commit 952266b6d64f923f9d6d4390e423e4ab65a953c6
• 2ca9c01 Updated Rector to commit da48be85d84c065d1f018c9074694980d2351e77
• Additional commits viewable in compare view

[pierredup]

@dependabot recreate