Fix for incorrect ticket count in query when running more than on provider.

[Camwyn]

Discovered while doing prelim work for presets. ETP-988
ET-2317

This line:
$args['meta_query'] = array_merge( (array) $args['meta_query'], (array) $module_args['meta_query'] );

Overwrites the relation set in $args with the default "AND"

So if we are running two providers (such as TC and RSVP) and we check for ticket IDs on a post (with an ID of 215 below) the final query will be:

$query = [
	[post_type]      => [
		[rsvp] => tribe_rsvp_tickets,
		[0]    => tec_tc_ticket,
	],
	[posts_per_page] => -1,
	[fields]          => ids,
	[post_status]    => publish,
	[order_by]       => menu_order,
	[order]          => ASC,
	[meta_query]     => [
		[relation]                       => AND,
		[_tribe_rsvp_for_event_in]       => [
			[key]     => _tribe_rsvp_for_event
			[compare] => IN
			[value]   => [ [0] => 215 ]

		
		],
		[_tec_tickets_commerce_event_in] => [
			[key]     => _tec_tickets_commerce_event
			[compare] => IN
			[value]   => [ [0] => 215 ]

		
		],
	]
];

Note the "AND" - so this will fail, and the function will always return 0 tickets found. It can't be both an RSVP AND a ticket (or a ticket from two providers simultaneously).

Also fixed the docblocks for get_tickets_ids() and the called Tribe__Tickets__Tickets::set_tickets_query_args() as neither can currently handle getting a post object passed to them 😞

[dpanta94]

This seems like a good change but kinda worried of what we might be breaking because of that. I would check ETP's test as well how they behave with that change in place.

[Camwyn]

This seems like a good change but kinda worried of what we might be breaking because of that. I would check ETP's test as well how they behave with that change in place.

PR: https://github.com/the-events-calendar/event-tickets-plus/pull/1770