Add remaining get_backdoor_port() rpc calls to coverage.

This adds the get_backdoor_port() rpc calls for cert, conductor,
console, consoleauth, and scheduler so that the coverage
extension can now telnet into all of those services.

Change-Id: I5de654a11ac224b1192a3b1601855c302b771efd
Merge "Add remaining get_backdoor_port() rpc calls to coverage."