minor #20504 Fix build (OskarStark)

This PR was merged into the 7.1 branch.

Discussion
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Fix build

```
security.rst ✘
    1: The following link definitions aren't used anymore and should be removed: "SensitiveParameter PHP attribute"
```

Commits
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0008e5b Fix build

Author: javiereguiluz

security.rst

@@ -2966,4 +2966,3 @@ Authorization (Denying Access)
 .. _`Login CSRF attacks`: https://en.wikipedia.org/wiki/Cross-site_request_forgery#Forging_login_requests
 .. _`PHP date relative formats`: https://www.php.net/manual/en/datetime.formats.php#datetime.formats.relative
 .. _`Oauth2-client`: https://github.com/thephpleague/oauth2-client
-.. _`SensitiveParameter PHP attribute`: https://www.php.net/manual/en/class.sensitiveparameter.php