Editing Woocommerce Includes

For Woocommerce Plugin, there is a function inside includes-> class-wc-order.php

I would want to edit this public function payment_complete( $transaction_id = ” )

For the apply_filters to add another order status from:

apply_filters( 'woocommerce_valid_order_statuses_for_payment_complete', array( 'on-hold', 'pending', 'failed', 'cancelled')

to

apply_filters( 'woocommerce_valid_order_statuses_for_payment_complete', array( 'on-hold', 'pending', 'failed', 'cancelled','verifying' )

Without editing the core files so I can still update the Woocommerce plugin.

I have tried to add them in my child theme Themes->”MYCUSTOMTHEMEFOLDER”->woocommerce->includes->class-wc-order.php

but it is still not working, any clue on how I can do this? It is only just one lines of code to edit