New requirement for WooCommerce 6.5: PHP 7.2+

It’s been a while since WooCommerce bumped the minimum PHP version of WooCommerce to 7.0, and the WooCommerce team believes that now is about time for a new bump. Starting with version 6.5, scheduled for release in May 2022, WooCommerce will require PHP 7.2 or newer to work.
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