Update dependency php/php-src

This MR contains the following updates:

Package	Type	Update	Change
php/php-src	ironbank-github	patch	php-8.1.20 -> php-8.1.21
php/php-src		patch	8.1.20 -> 8.1.21

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Release Notes

php/php-src

vphp-8.1.21

Compare Source

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