We are lagging behind the Operator SDK version and right now we are on v0.18.2. Since v0.19, the Operator SDK has adopted the Kubebuilder project structure. We need to restructure the project and migrate the tests to embrace a newer version. That will bring us the benefits of using Kustomize, enabling webhooks, and ket the libraries updated according to the supported Openshift Versions.

Upstream issue: https://github.com/wildfly/wildfly-operator/issues/216

Accordingly to this document and the general policy for Middleware product support on OpenShift, we need to support at minimum OpenShift 4.6:
https://access.redhat.com/articles/5702651

In terms of Operator SDK, we should migrate at maximum to Operator SDK v1.3.x. That will ensure we are using a tested Client Go version (v0.19.2) to talk to OpenShift v4.6 (Kubernetes v0.19)