Stack traces missing from inner exceptions of aggregate exceptions

[mattjohnsonpint]

SDK Version

3.21.0

Steps to Reproduce

using Sentry;

using (SentrySdk.Init(o =>
       {
           o.Dsn = "https://eb18e953812b41c3aeb042e666fd3b5c@o447951.ingest.sentry.io/5428537";
           o.Debug = true;
       }))
{
    throw new AggregateException(new MyException());
}

public class MyException : Exception
{
}

Expected Result

The AggregateException should be filtered out, and Sentry should capture the unhandled MyException, retaining the stack trace.

Actual Result

The AggregateException is filtered out, but the stack trace is gone also.

We need to copy over the stack trace when filtering out aggregate exceptions.

[mattjohnsonpint]

Also missing mechanism and extra data. These are only left on the aggregate, so they need to be copied over to the last exception sent to Sentry. (Sentry expects exceptions from oldest to newest.)