Expose a function that tells us if our enclave runs in debug mode

[NullHypothesis]

One way to go about this is to ask for an attestation document and check if its PCR values are set. An enclave that's launched in debug mode has all its PCR values zeroed out. Perhaps there's a smarter way to do that, without having to rely on the PCR side effect.

This would let us set the Config.Debug key automatically without the user having to rebuild the application to access debug logs.