Fix code block syntax

Author: GaneshChandrasekaran-zz

components/lock.rst

@@ -290,7 +290,7 @@ ZookeeperStore
 The ZookeeperStore saves locks on a Zookeeper server, it requires a Zookeeper
 connection implementing the ``\Zookeeper`` class. This store does not
 support blocking and expiration but the lock is automatically released when the
-PHP process is terminated
+PHP process is terminated::
 
     use Symfony\Component\Lock\Store\ZookeeperStore;
 
@@ -519,7 +519,7 @@ can be two running containers in parallel.
 ZookeeperStore
 ~~~~~~~~~~
 
-The way ZookeeperStore works is by maintaining locks in ephemeral nodes within PHP_LOCK_NODE on the server. That means that by using
+The way ZookeeperStore works is by maintaining locks in ephemeral nodes within `PHP_LOCK_NODE` on the server. That means that by using
 the :ref:`ZookeeperStore <lock-store-zookeeper>` the locks will be automatically released at the end of the session
 in case the client cannot unlock for any reason.