bug symfony#51821 Add test for 0 and '0' in PeriodicalTrigger and fix '0' case error (ardentsword)

This PR was merged into the 6.4 branch.

Discussion
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Add test for 0 and '0' in PeriodicalTrigger and fix '0' case error

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       |
| License       | MIT

While taking a peek at the code I found the possibility for this case slipping by the error checking.
To prevent code duplication I took the liberty to also merge the two checks since they are so similar.

Please let me know if there is any feedback on my pull request or if there are any questions.

Commits
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14f827b Add test for 0 and '0' in PeriodicalTrigger Fix '0' case error and remove duplicate code

Author: fabpot

src/Symfony/Component/Scheduler/Tests/Trigger/PeriodicalTriggerTest.php

@@ -73,6 +73,8 @@ public static function getInvalidIntervals(): iterable
         yield ['3600.5'];
         yield ['-3600'];
         yield [-3600];
+        yield ['0'];
+        yield [0];
     }
 
     /**

src/Symfony/Component/Scheduler/Trigger/PeriodicalTrigger.php

@@ -30,18 +30,11 @@ public function __construct(
         $this->from = \is_string($from) ? new \DateTimeImmutable($from) : $from;
         $this->until = \is_string($until) ? new \DateTimeImmutable($until) : $until;
 
-        if (\is_int($interval) || \is_float($interval)) {
-            if (0 >= $interval) {
+        if (\is_int($interval) || \is_float($interval) || \is_string($interval) && ctype_digit($interval)) {
+            if (0 >= (int) $interval) {
                 throw new InvalidArgumentException('The "$interval" argument must be greater than zero.');
             }
 
-            $this->intervalInSeconds = $interval;
-            $this->description = sprintf('every %d seconds', $this->intervalInSeconds);
-
-            return;
-        }
-
-        if (\is_string($interval) && ctype_digit($interval)) {
             $this->intervalInSeconds = (int) $interval;
             $this->description = sprintf('every %d seconds', $this->intervalInSeconds);