minor symfony#21120 [Scheduler] Document unique schedule name (mttsch)

This PR was merged into the 7.4 branch.

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[Scheduler] Document unique schedule name

Fix symfony#21024

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8a6a9f2 [Scheduler] Document unique schedule name

Author: javiereguiluz

scheduler.rst

@@ -133,9 +133,14 @@ on a particular schedule::
 
 .. tip::
 
-    By default, the schedule name is ``default`` and the transport name follows
+    The schedule name must be unique and by default, it is ``default``. The transport name follows
     the syntax: ``scheduler_nameofyourschedule`` (e.g. ``scheduler_default``).
 
+.. versionadded:: 7.4
+
+    Throwing an exception for duplicate schedule names instead of replacing the existing schedule
+    was introduced with Symfony 7.4.
+
 .. tip::
 
     `Memoizing`_ your schedule is a good practice to prevent unnecessary reconstruction