Port https://github.com/dotnet/sdk/pull/3427 by @peterhuene with my edit

This commit deletes the output apphost when the CreateAppHost task fails from
an exception.

Partially fixes dotnet/core-setup#2989

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* deletes the output apphost when the `CreateAppHost` task fails from
an exception.

* aggreates the Exception for future logging from deleting the failed apphost


Commit migrated from https://github.com/dotnet/core-setup/commit/7f0eb2869f2f37a899cdd02b7bbc4bd78e4e7038