MTE creates engines more than once for some tests

[keturn]

On an MTE test that has a @BeforeAll method or that uses field injection with @In, MTE can end up creating more than one set of engines. Something to do with how the postProcessTestInstance method doesn't get a testInstance in its context, but then later when something else does parameter injection on a @BeforeEach or @Test method, it does know the instance, and the way I wrote it stored those under different keys and now there are too many things.

Reproduction test case in #5039.

While addressing this, we might also revisit Terasology/ModuleTestingEnvironment#75
Drop our own @IsolatedMTEExtension stuff and have test authors use Lifecycle.PER_CLASS if they want engines shared between test methods?

[keturn]

There's some bookkeeping code to catch this off in an experimental branch:

[ MTEExtension.java ]

Terasology/engine-tests/src/main/java/org/terasology/engine/integrationenvironment/jupiter/MTEExtension.java

Lines 221 to 250 in 6b64317

	static class EnginesCleaner implements ExtensionContext.Store.CloseableResource {
	@SuppressWarnings("checkstyle:ConstantName")
	private static final AtomicInteger engineCount = new AtomicInteger();
	protected Engines engines;
	final Boolean soleEngineAtCreation;
	EnginesCleaner(Set<String> dependencyNames, String worldGeneratorUri, NetworkMode networkMode,
	List<Class<? extends EngineSubsystem>> subsystems) {
	int currentCount = engineCount.incrementAndGet();
	soleEngineAtCreation = currentCount == 1;
	logger.debug("About to create new engine. Total: {}", currentCount);
	try {
	engines = new Engines(dependencyNames, worldGeneratorUri, networkMode, subsystems);
	engines.setup();
	} catch (Exception e) {
	currentCount = engineCount.decrementAndGet();
	logger.debug("Engine creation failed. Total: {}", currentCount);
	throw e;
	}
	}
	@Override
	public void close() {
	engines.tearDown();
	engines = null;
	logger.debug("Tore down an engine. Total: {}", engineCount.decrementAndGet());
	}
	}