Refactor: CTS: Update add_cmd calls in cts-attrd.

These need to be updated for the changes to the Test class.

• Handle arguments after the command as kwargs.

• Clean up some of the quoting used when calling these functions. I haven't addressed the problems throughout the file, just in the callers I was already modifying. Basically, change double quotes to single quotes so we can reduce some of the unnecessary escaping.