minor symfony#17581 [Ldap] Remove unused private property (paradajozsef)

This PR was merged into the 2.8 branch.

Discussion
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[Ldap] Remove unused private property

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Commits
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e685305 [Ldap] Remove unused private property

Author: fabpot

src/Symfony/Component/Ldap/LdapClient.php

@@ -30,7 +30,6 @@ class LdapClient implements LdapClientInterface
     private $useStartTls;
     private $optReferrals;
     private $connection;
-    private $charmaps;
 
     /**
      * Constructor.