…recated notice (maxhelias)

This PR was merged into the 4.3 branch.

Discussion
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[SecurityBundle] display the correct class name on the deprecated notice

| Q             | A
| ------------- | ---
| Branch?       | 4.3 <!-- see below -->
| Bug fix?      | yes
| New feature?  |no <!-- please update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? |no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | -  <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | - <!-- required for new features -->

<!--
Replace this notice by a short README for your feature/bugfix. This will help people
understand your PR and can be used as a start for the documentation.

Additionally (see https://symfony.com/roadmap):
 - Bug fixes must be submitted against the lowest maintained branch where they apply
   (lowest branches are regularly merged to upper ones so they get the fixes too).
 - Features and deprecations must be submitted against branch 4.4.
 - Legacy code removals go to the master branch.
-->

Commits
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8e64b9a [SecurityBundle] display the correct class name on the deprecated notice