I am using gitlab, though we quickly grew beyond auto devops.
Your definition of auto devops is different than gitops. Gitops is the practice of using commits and pull requests to execute change and do releases. Weave uses it to mean git as the source of truth. https://www.weave.works/blog/gitops-operations-by-pull-reque... Kelsey Hightower talked about it and and has demoed the workflow of using pull requests to initiate promotion and deployments.
Gitlab's auto devops does not seem to tackle promotion via environment repos, so in my understanding does not fit gitops and would be confusing to call it such.
Edit: Kelsey Hightower's kubeconf talk - https://www.youtube.com/watch?v=07jq-5VbBVQ
And a better writeup on weave's site -https://www.weave.works/blog/gitops-high-velocity-cicd-for-k...
Don't get me wrong, I think auto devops is a good thing, but it's most certainly not gitops.
To add to that, GitOps as defined by Weaveworks and Kelsey Hightower is a technology agnostic approach.