feature #8082 [Stopwatch] Document the reset method (jmgq)

This PR was merged into the master branch.

Discussion
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[Stopwatch] Document the reset method

Documentation for the new `Stopwatch::reset` method described in symfony/symfony#23284.

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4b21133 [Stopwatch] Document the reset method

Author: xabbuh

components/stopwatch.rst

@@ -41,6 +41,10 @@ from the  :method:`Symfony\\Component\\Stopwatch\\Stopwatch::start`,
 The latter should be used when you need to retrieve the duration of an event
 while it is still running.
 
+The stopwatch can be reset to its original state at any given time with the
+:method:`Symfony\\Component\\Stopwatch\\Stopwatch::reset` method, which deletes
+all the data measured so far.
+
 You can also provide a category name to an event::
 
     $stopwatch->start('eventName', 'categoryName');