Execute `woocommerce_order_action_{$action}` only once

Prevents a “Maximum function nesting level reached” fatal error in
certain cases.

Since this ends up running on `’save_post’`, updating something like
the order status while hooked onto to
`woocommerce_order_action_{$action}` causes a fun recursion :)
Merge pull request #6875 from tamarazuk/limit-order-action

Execute `woocommerce_order_action_{$action}` only once