ABFS handles nonexistent/non-auth accounts badly

Testing storediag with a nonexistent account/bucket raises interesting failures modes

1. DNS failures are retried, rather than fail fast
2. a container which exists but you can't access fails with the wrong exception

org.apache.hadoop.fs.FileAlreadyExistsException: Operation failed: "This endpoint does not support BlobStorageEvents or SoftDelete. Please disable these account features if you would like to use this endpoint.", 409, HEAD, https://somewhere.dfs.core.windows

Proposed

1. failfast on host not found, escalate to an account not found
2. recognise and translate that does not support BlobStorageEvents

side issue: is that failure leaking secrets about another a/c? or is it always raised if not authed