minor #62519 [HttpFoundation] Fix Request getPathInfo docblock (bobvandevijver)

This PR was merged into the 6.4 branch.

Discussion
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[HttpFoundation] Fix Request getPathInfo docblock

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | yes
| New feature?  | no <!-- if yes, also update src/**/CHANGELOG.md -->
| Deprecations? | no <!-- if yes, also update UPGRADE-*.md and src/**/CHANGELOG.md -->
| Issues        | -
| License       | MIT

Fix incorrect example in `getPathInfo` docblock. It's return value will always start with `/`, so the first example cannot be an empty string.

While this is also valid for 5.4 (and was fixed there as part of CVE-2025-64500, I'm now only submitting it for 6.4.

Commits
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fe802d288d6 Fix Request getPathInfo docblock

Author: nicolas-grekas

Request.php

@@ -857,7 +857,7 @@ public function getScriptName(): string
      *
      * Suppose this request is instantiated from /mysite on localhost:
      *
-     *  * http://localhost/mysite              returns an empty string
+     *  * http://localhost/mysite              returns '/'
      *  * http://localhost/mysite/about        returns '/about'
      *  * http://localhost/mysite/enco%20ded   returns '/enco%20ded'
      *  * http://localhost/mysite/about?var=1  returns '/about'