Hi Michael,
The adapt-cli currently does not support unregistering of components. However, bower has recently implemented support for this, and so adapt-cli may soon support it also. Perhaps you can create an issue on https://github.com/adaptlearning/adapt-cli to kickstart this feature? In the meantime, you may be able to use bower to unregister the component, although I have not tested this.
Try the following commands:
$ npm install -g bower
$ cd /path/to/my/project
$ bower unregister my-component-name
I'd be interested to know if this works for you. If you decide to try this, please post back your result.