minor #8845 [Lock] Add an auto release tips (jderusse, javiereguiluz)

This PR was merged into the 3.4 branch.

Discussion
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[Lock] Add an auto release tips

Commits
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beb9a6e Reword
69bdba4 Add the auto release tips

Author: javiereguiluz

components/lock.rst

@@ -62,6 +62,13 @@ method can be safely called repeatedly, even if the lock is already acquired.
     to be used by several services, they should share the same ``Lock`` instance
     returned by the ``Factory::createLock`` method.
 
+.. tip::
+
+    If you don't release the lock explicitly, it will be released automatically
+    on instance destruction. In some cases, it can be useful to lock a resource
+    across several requests. To disable the automatic release behavior, set the
+    third argument of the ``createLock()`` method to ``false``.
+
 Blocking Locks
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