I've begun a GitOps journey with k8s and argoCD using separate repos for app source and deployment files (manifests, environment config, etc), and I'm trying to figure out, how I would ensure a succesful deployment, if an application source code change also requires a change in environment config.

Example: an application is deployed and running on a test/QA environment, and I want to push a code change, which requires a new "DB_ConnectionString" environment variable. Since this environment variable is new, it doesn't exist in my deployment/gitops repo's config files (let's say it's a Helm values-QA.yml).

If I push this new code change, the CI will build the application and update the container, which prompts argoCD to deploy the new container version - but because I haven't updated the GitOps repo, it's missing this new variable, and the deployment will fail.

I guess I'm struggling to understand, if in these cases, I'm forced to always ensure that my GitOps repo is updated before my app repo, and whether there's a best practice to handle this flow?