Installation with PIE

[arokettu]

PIE is the new official extension installer for PHP, and PECL is being deprecated

• https://github.com/php/pie
• https://wiki.php.net/rfc/adopt_pie_deprecate_pecl

Please enable installation with PIE

relevant doc: https://github.com/php/pie/blob/main/docs/extension-maintainers.md

[arokettu]

I looked through issues and forgot to look through MRs. Look like there is already an MR for that: #95