minor #19019 [Serializer] Update reference to attribute in the section title (FlyingDR)

This PR was squashed before being merged into the 6.3 branch.

Discussion
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[Serializer] Update reference to attribute in the section title

Symfony 6 uses attributes instead of annotations, but reference to the ``@Ignore`` annotation still remains in the section title.

Commits
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5a7bc8e [Serializer] Update reference to attribute in the section title

Author: javiereguiluz

components/serializer.rst

@@ -441,8 +441,8 @@ Ignoring Attributes
 All attributes are included by default when serializing objects. There are two
 options to ignore some of those attributes.
 
-Option 1: Using ``@Ignore`` Annotation
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Option 1: Using ``#[Ignore]`` Attribute
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. configuration-block::