minor #7591 simple typo (appeltaert)

This PR was submitted for the 3.2 branch but it was merged into the 2.7 branch instead (closes #7591).

Discussion
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simple typo

Commits
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75abc27 simple typo

Author: xabbuh

components/dom_crawler.rst

@@ -79,7 +79,7 @@ This allows you to use jQuery-like selectors to traverse::
 
     $crawler = $crawler->filter('body > p');
 
-Anonymous function can be used to filter with more complex criteria::
+An anonymous function can be used to filter with more complex criteria::
 
     use Symfony\Component\DomCrawler\Crawler;
     // ...