minor #48793 Leverage arrow function syntax for closure (tigitz)

This PR was merged into the 6.3 branch.

Discussion
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Leverage arrow function syntax for closure

| Q             | A
| ------------- | ---
| Branch?       | 6.3
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix #47658 <!-- prefix each issue number with "Fix #", no need to create an issue if none exists, explain below instead -->
| License       | MIT
| Doc PR        | <!-- required for new features -->

Rationale in the RFC [here](https://wiki.php.net/rfc/arrow_functions_v2#introduction)

It's also notable that using arrow function syntax rather than the classic one has been enforced in the past by symfony core member: symfony/symfony#48069 (comment)

So this PR would be consistent.

Commits
-------

f5802d3a2a Leverage arrow function syntax for closure

Author: nicolas-grekas

Tests/AbstractCrawlerTest.php

@@ -262,9 +262,7 @@ public function testNormalizeWhiteSpace()
 
     public function testEach()
     {
-        $data = $this->createTestCrawler()->filterXPath('//ul[1]/li')->each(function ($node, $i) {
-            return $i.'-'.$node->text();
-        });
+        $data = $this->createTestCrawler()->filterXPath('//ul[1]/li')->each(fn ($node, $i) => $i.'-'.$node->text());
 
         $this->assertEquals(['0-One', '1-Two', '2-Three'], $data, '->each() executes an anonymous function on each node of the list');
     }
@@ -290,9 +288,7 @@ public function testSlice()
     public function testReduce()
     {
         $crawler = $this->createTestCrawler()->filterXPath('//ul[1]/li');
-        $nodes = $crawler->reduce(function ($node, $i) {
-            return 1 !== $i;
-        });
+        $nodes = $crawler->reduce(fn ($node, $i) => 1 !== $i);
         $this->assertNotSame($nodes, $crawler, '->reduce() returns a new instance of a crawler');
         $this->assertInstanceOf(Crawler::class, $nodes, '->reduce() returns a new instance of a crawler');