Fix CursorId and Event::getServer() deprecation in tests

[GromNaN]

Related to #1366

[GromNaN]

I added fixes for calls to Event::getServer(), using getServerConnectionId() instead.
But for the FailPointsOberver, I need an actual Server instance. This requires a larger refactoring.

mongo-php-library/tests/UnifiedSpecTests/FailPointObserver.php

Line 36 in b27a61d

$this->failPointsAndServers[] = [$command->configureFailPoint, $event->getServer()];

mongo-php-library/tests/UnifiedSpecTests/FailPointObserver.php

Lines 46 to 49 in b27a61d

	foreach ($this->failPointsAndServers as [$failPoint, $server]) {
	$operation = new DatabaseCommand('admin', ['configureFailPoint' => $failPoint, 'mode' => 'off']);
	$operation->execute($server);
	}

Tracked in PHPLIB-1531

[GromNaN]

This logs and the $eventList property are never used. They can be useful for debugging.

[jmikola]

Quoting the Workload Executor Specification from drivers-atlas-testing:

each object is expected to have a name string field and an observedAt numeric field, in addition to any other fields specific to the event's type.

The only other field here that corresponds to an existing field in the Unified Test Format spec's expectedEvent section is commandName. That said, I think the original intention of connectionId here was from the client's perspective, so this should also change to a host/port combination. I'd also propose renaming this to server and adding serverConnectionId (which may not have existed at the time we implemented Atlas testing). I'll address that in my forthcoming PR to address my other feedback.

[jmikola]

See: #1428

[jmikola]

Later, this was used for the following assertion:

/* Step 6: Assert that two failed command events occurred. Assert that
 * the failed command events occurred on different mongoses. */

Per getServerConnectionId(), the connection ID is unique within the context of a single server. It is also only reported by MongoDB 4.2+. I think the correct change here would have been to replace getServer() with a concatenation of the server host/port. I'll make the change in a subsequent PR.

As-is, I think this might sometimes fail if both mongoses reported the same connection ID or if we test on mongos 4.0.

[jmikola]

This relates the following assertion:

/* Step 6: Assert that exactly one failed command event and one
 * succeeded command event occurred. Assert that both events occurred on
 * the same mongos. */

Those rely on assertNotNull(), so this could also fail on a 4.0 server where connection IDs are not reported.