fix: Collect MainThreadData first thing in Init

[bitsandfoxes]

Fixes #2247

Since the native configuration now gets called from within the SDK it does not need to be pulled out into Android.Configure and can universally be the first thing the SDK does.

This works because Init is getting automatically called in SentryInitialization.cs

sentry-unity/package-dev/Runtime/SentryInitialization.cs

Lines 58 to 71 in c46352d

	private static void Init()
	{
	// We're setting up `UnityInfo` and the platform specific configure callbacks as the very first thing.
	// These are required to be available during initialization.
	SetUpPlatformServices();
	// Loading the options invokes the ScriptableOption`Configure` callback. Users can disable the SDK via code.
	var options = ScriptableSentryUnityOptions.LoadSentryUnityOptions();
	if (options != null && options.ShouldInitializeSdk())
	{
	SentrySdk.Init(options);
	}
	else
	{

#skip-changelog

[limbonaut]

LGTM