https://docs.redhat.com/en/documentation/red_hat_openshift_gitops/1.15/html/argo_cd_applications/deploying-a-spring-boot-application-with-argo-cd#creating-an-application-by-using-the-argo-cd-dashboard_deploying-a-spring-boot-application-with-argo-cd

In the above section for installing openshift-gitops sample app spring-petclinic, need to add the following steps:

When using Argo CD UI:

• make sure "Auto Create Namespace" is selected, so that the destination namespace "spring-petclinic" will be created while creating the argocd application.

When using oc command line, add the following steps:

• before creating the application, first need to create and configure the destination namespace

  oc create namespace spring-petclinic
  oc label namespace spring-petclinic argocd.argoproj.io/managed-by=openshift-gitops
  

• optionally, it will be good to delete the app and namesapce after everything is done:

  oc delete -n openshift-gitops -f openshift-gitops-getting-started/argo/app.yaml
  oc delete namespace spring-petclinic