Moving WooCommerce Images to ACF Repeater subfields

functions.php

add_action( 'init', 'test_update_products' );

function test_update_products() {
  // You can use offset if needed.
	$args = array(
		'post_type'   => 'my_awesome_cpt',
		'numberposts' => 300,
		//'offset'      => 1000,
	);

	$my_posts = get_posts( $args );

	foreach ( $my_posts as $my_post ) {
		my_acf_save_post( $my_post->ID );
	}
}

function my_acf_save_post( $post_id ) {
  // is used the ACF Repeater keys here, but didn't need it for the subfield below.
	$repeater_field_key = 'field_5d95181ce7407';
	$sub_field_key = 'field_5d951835e7408';
	$media = get_attached_media( 'image', $post_id );
	$value_array = [];
	$counter = 0;
	foreach ( $media as $m ) {
		$value_array[ $counter ] = array(
			'gallery_image' => $m->ID,
		);
		$counter++;
	}
	update_field( $repeater_field_key, $value_array, $post_id );

}