minor #14000 [Stopwatch] Add name property to the stopwatchEvent (AhmedRaafat14)

This PR was squashed before being merged into the master branch.

Discussion
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[Stopwatch] Add name property to the stopwatchEvent

Q | A
-- | --
Branch? | master for features
Bug fix? | no
New feature? | yes
Deprecations? | no
Tickets | Fix  #14051

Commits
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5d971ee [Stopwatch] Add name property to the stopwatchEvent

Author: javiereguiluz

components/stopwatch.rst

@@ -102,6 +102,7 @@ For example::
     $event->getEndTime();    // returns the end time of the very last period
     $event->getDuration();   // returns the event duration, including all periods
     $event->getMemory();     // returns the max memory usage of all periods
+    $event->getName();       // returns the event name
 
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