bug #19798 fix warning for number constraints with PHP 7.x (alexislefebvre)

This PR was merged into the 5.4 branch.

Discussion
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fix warning for number constraints with PHP 7.x

Fixes display issue on https://symfony.com/doc/5.x/reference/constraints/Positive.html

> ![image](https://github.com/symfony/symfony-docs/assets/2071331/1f38acb6-950f-4837-9ae5-0f9074d49b8f)

`integer` is not displayed as code.

- Follow-up of #19765

Commits
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02e88f1 Update _php7-string-and-number.rst.inc

Author: OskarStark

reference/constraints/_php7-string-and-number.rst.inc

@@ -3,4 +3,4 @@
     When using PHP 7.x, if the value is a string (e.g. ``1234asd``), the validator
     will not trigger an error. In this case, you must also use the
     :doc:`Type constraint </reference/constraints/Type>` with
-    ``numeric``, ``integer`, etc. to reject strings.
+    ``numeric``, ``integer``, etc. to reject strings.