[CD12] doc chapter 2.2. Prepare OpenShift for Application Deployment updates

EAP doc chapter 2.2. Prepare OpenShift for Application Deployment needs following updates:

• Step 3 "Create a service account for this deployment" should be removed
• Step 4 "Add the view role to the service account." should be removed
• Step 6 - the secret name should be eap7-app-secret instead of eap-app-secret
• Step 7 "Add the secret to the service account. " should be removed