minor #4873 [BestPractices] fix minor typo (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[BestPractices] fix minor typo

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Commits
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b8ed4b7 [BestPractices] fix minor typo

Author: wouterj

Diff for: best_practices/security.rst

@@ -128,7 +128,7 @@ Security Voters
 
 If your security logic is complex and can't be centralized into a method
 like ``isAuthor()``, you should leverage custom voters. These are an order
-of magnitude easier than :doc:`ACL's </cookbook/security/acl>` and will give
+of magnitude easier than :doc:`ACLs </cookbook/security/acl>` and will give
 you the flexibility you need in almost all cases.
 
 First, create a voter class. The following example shows a voter that implements