minor #20162 [Security] adding missing 'private' (tacman)

This PR was submitted for the 7.1 branch but it was merged into the 6.4 branch instead.

Discussion
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[Security] adding missing 'private'

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Commits
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fae9a57 adding missing 'private'

Author: javiereguiluz

security.rst

@@ -2620,7 +2620,7 @@ want to include extra details only for users that have a ``ROLE_SALES_ADMIN`` ro
       class SalesReportManager
       {
     +     public function __construct(
-    +         Security $security,
+    +         private Security $security,
     +     ) {
     +     }