EventPipe shutdown too early

[jkotas]

EventPipe::Shutdown + DiagnosticServer::Shutdown is called as the first thing in EEShutDownHelper: https://github.com/dotnet/coreclr/blob/5b283a18625f7a8009c18221592ec81c3cd32375/src/vm/ceemain.cpp#L1409

This is too early. There is still quite a bit of user managed code running during EEShutDownHelper (all AppDomain.ProcessExit events) that should be able to use tracing facilities.