Add SentrySdk.RunAsyncVoid helper method to Sentry SDK

[jamescrosswell]

See https://www.jamescrosswell.dev/posts/catching-async-void-exceptions/

For Sentry, by default we could capture the exception and send it to sentry... and optionally invoke any user defined callback (if one was supplied).

I just wanted something like this in a button click handler in Maui (that needed to call some async methods on HttpClient - no blocking versions of those methods exist).