CI Failures from forks

[rwjblue]

Folks sending in a PR from their local forks will always cause a failure of the ember-cli-update CI job. This is due to the usage of ${{ secrets.GitHubToken }} here:

ember-cli-update/.github/workflows/ci.yml

Lines 72 to 73 in fc221be

	ref: ${{ github.head_ref }}
	token: ${{ secrets.GitHubToken }}

Pull requests from forks will not have access to any ${{ secrets.* }} content (for somewhat clear security reasons).

See documentation here, which starts out with:

With the exception of GITHUB_TOKEN, secrets are not passed to the runner when a workflow is triggered from a forked repository.