The package ember-cli-self-update is not a properly formatted package, we have used a fallback lookup to resolve it at /project/node_modules/ember-cli-self-update. This is generally caused by an addon not having a main entry point (or index.js).
The ember-cli-self-update addon could not be found at /project/node_modules/ember-cli-self-update.
$ ember install ember-cli-self-update