minor #20300 [Console] Document FinishedIndicator for Progress indicator (Jibbarth)

This PR was merged into the 7.2 branch.

Discussion
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[Console] Document FinishedIndicator for Progress indicator

Hello 👋

 I give a try to fix #20296

Commits
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861a096 [Console] Document FinishedIndicator for Progress indicator

Author: javiereguiluz

components/console/helpers/progressindicator.rst

@@ -95,6 +95,26 @@ The progress indicator will now look like this:
      ⠹ Processing...
      ⢸ Processing...
 
+Custom Finished Indicator
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Once the progress indicator is finished, it keeps by default the latest indicator value. You can replace it with a your own::
+
+    $progressIndicator->finish('Finished', '✅');
+
+Then the progress indicator will render like this:
+
+.. code-block:: text
+
+     ⠏ Processing...
+     ⠛ Processing...
+     ✅ Finished
+
+.. versionadded:: 7.2
+
+    The ``finishedIndicator`` parameter for method ``finish()`` was introduced in Symfony 7.2.
+
+
 Customize Placeholders
 ~~~~~~~~~~~~~~~~~~~~~~