minor symfony#10184 added a space before "=" in code (scuben)

This PR was submitted for the 4.1 branch but it was merged into the 3.4 branch instead (closes symfony#10184).

Discussion
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added a space before "=" in code

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Commits
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f569614 added a space before "=" in code

Author: weaverryan

components/lock.rst

@@ -248,7 +248,7 @@ then the lock is considered as acquired; otherwise as not acquired::
 
     $stores = [];
     foreach (array('server1', 'server2', 'server3') as $server) {
-        $redis= new \Redis();
+        $redis = new \Redis();
         $redis->connect($server);
 
         $stores[] = new RedisStore($redis);