Make async overloads of DiagnosticsClient public

[ezsilmar]

Hello, I'm facing the issue described in #2151: for some reason EventPipeSession.Start is stuck indefinitely in IPC parsing. This issue was resolved by introducing StartAsync overloads in #2350

However, these overloads are internal. I'd be happy to use them to pass the cancellation token and cleanup the session in this case.

[hoyosjs]

@tommcdon

[tommcdon]

Hello @ezsilmar! Thanks for reporting this issue. Please feel free to submit a PR adding the appropriate public overloads and we will take a look. Otherwise, we will add this item to our team's backlog.

[emz00]

This would be useful for us as well! PR: #4394