minor #29396 fix type for $value in DocBlock (rudidude86)

This PR was submitted for the master branch but it was merged into the 3.4 branch instead (closes #29396).

Discussion
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fix type for $value in DocBlock

`$value` is supposed to be a string, not an int, according to [`NumberFormatter::setTextAttribute()` documentation](https://secure.php.net/manual/en/numberformatter.settextattribute.php)

| Q             | A
| ------------- | ---
| Branch?       | master for features / 3.4 up to 4.2 for bug fixes <!-- see below -->
| Bug fix?      | yes/no
| New feature?  | yes/no <!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | yes/no <!-- don't forget to 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        | symfony/symfony-docs#... <!-- required for new features -->

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Commits
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ff2431a512 fix type for $value in DocBlock

src/Symfony/Component/Intl/NumberFormatter/NumberFormatter.php

@@ -639,7 +639,7 @@ class NumberFormatter
      * Not supported. Set a text attribute.
      *
      * @param int $attr  An attribute specifier, one of the text attribute constants
-     * @param int $value The attribute value
+     * @param string $value The attribute value
      *
      * @return bool true on success or false on failure
      *