minor #21069 [Security] fix: use correct function and parameter name (alessandro-podo, Alessandro Podo)

This PR was merged into the 6.4 branch.

Discussion
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[Security] fix: use correct function and parameter name

#21040

while merging this, the same function name was used 2 times.

Commits
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2ee7578 fix missing $
c8b6263 fix: use correct function and parameter name

Author: javiereguiluz

security/voters.rst

@@ -331,7 +331,7 @@ Then, override one or both of the following methods::
 
         // this method returns true if the voter applies to the given object class/type;
         // if it returns false, Symfony won't call it again for that type of object
-        public function supportsAttribute(string $attribute): bool
+        public function supportsType(string $subjectType): bool
         {
             // you can't use a simple Post::class === $subjectType comparison
             // because the subject type might be a Doctrine proxy class