minor #19980 [Lock] Update lock.rst (gus3000)

This PR was merged into the 5.4 branch.

Discussion
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[Lock] Update lock.rst

Incorrect assumption that $lock->getRemainingLifetime()'s unit was minutes instead of seconds

This typo is also present in versions 6.4 and 7.* of the documentation.

Commits
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e3b2563 Update lock.rst

Author: javiereguiluz

components/lock.rst

@@ -788,7 +788,7 @@ Using the above methods, a robust code would be::
             $lock->refresh();
         }
 
-        // Perform the task whose duration MUST be less than 5 minutes
+        // Perform the task whose duration MUST be less than 5 seconds
     }
 
 .. caution::