minor #19895 [Scheduler] Update scheduler: Fixes the code in the Custom Triggers example (kells64000)

This PR was merged into the 6.4 branch.

Discussion
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[Scheduler] Update scheduler: Fixes the code in the Custom Triggers example

The while was missing a parenthesis and the negation of the condition needs to be removed for it to work as expected.

Commits
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ca65006 Update scheduler.rst

Author: javiereguiluz

scheduler.rst

@@ -320,7 +320,7 @@ For example, if you want to send customer reports daily except for holiday perio
             }
 
             // loop until you get the next run date that is not a holiday
-            while (!$this->isHoliday($nextRun) {
+            while ($this->isHoliday($nextRun)) {
                 $nextRun = $this->inner->getNextRunDate($nextRun);
             }