Update lock.rst

Author: atailouloute

components/lock.rst

@@ -356,7 +356,7 @@ accomplished, then the lock can be released by the store and acquired by
 someone else.
 
 The ``Lock`` provides several methods to check its health. The ``isExpired()``
-method checks whether or not it lifetime is over and the ``getRemainingLifetime()``
+method checks whether or not its lifetime is over and the ``getRemainingLifetime()``
 method returns its time to live in seconds.
 
 Using the above methods, a more robust code would be::