Fix: Suspend Android native support on Mono

[bitsandfoxes]

"Fix" is a bit of a stretch. More like "disabling it to prevent crashes".
The support was enabled with 0.18.0 and works for throwing Exceptions. But actually triggering a NullReferenceException i.e.

// Ends up on sentry-native and crashes the game
public void Start()
{
    TextAsset text = null;
    var bytes = text.bytes;
}

// Does not crash
public void Start()
{
    throw null;
}

// Does not crash
public void Start()
{
    throw new NullReferenceException();
}

ends up on the signal handler, ending up in sentry-native and causing the app to crash due to a C# exception.

[github-actions]

	Fails
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- Suspend Android native support on Mono ([#1362](https://github.com/getsentry/sentry-unity/pull/1362))

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