minor symfony#8143 Syntax error in documentation example (ciajulius)

This PR was merged into the 3.3 branch.

Discussion
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Syntax error in documentation example

Added curly brace where it was missing in code example

Commits
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a760613 Syntax error in documentation example

Author: xabbuh

security/api_key_authentication.rst

@@ -593,7 +593,7 @@ current URL is before creating the token in ``createToken()``::
             // set the only URL where we should look for auth information
             // and only return the token if we're at that URL
             $targetUrl = '/login/check';
-            if ($request->getPathInfo() !== $targetUrl)
+            if ($request->getPathInfo() !== $targetUrl) {
                 return;
             }