Changeset 52039 for trunk/tests/phpunit/tests/compat/strContains.php

General: Introduce polyfill for str_contains() added in PHP 8.0.

PHP 8.0 introduced a new function: str_contains(). It performs a case-sensitive check indicating if given substring (needle) is contained in the string to search in (haystack).

This polyfill makes this function available for use in Core.

Ref:

• PHP RFC ​https://wiki.php.net/rfc/str_contains
• PHP manual ​https://www.php.net/manual/en/function.str-contains.php

Props ayeshrajans, costdev, desrosj, hellofromTonya, knutsp, pbearne.
Fixes #49652.