test: Add CCA guest test
Add a test that launches a CCA guest and obtains an attestation token from RMM
Two slightly unrelated patches add --dry-run and --config to test.py, making it easier to run individual tests.
Add a test that launches a CCA guest and obtains an attestation token from RMM
Two slightly unrelated patches add --dry-run and --config to test.py, making it easier to run individual tests.