installer: Fix some typos in workflow/workflow.go

[felixonmars]

No description provided.

[openshift-ci-robot]

Hi @felixonmars. Thanks for your PR.

I'm waiting for a openshift member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[eparis]

Please send any PRs to github.com/coreos/tectonic-installer. We are in the process of figuring out how to transition, but for now, this repo is just a copy of that repo.