WIP: Site install with tekton tasks

Make Drupal site installation done with Tekton tasks

The site installation task is expected to change the Status.Condition "Installed" to True on the DrupalSiteCR when successful.

Still to do:

• Remove monitoring the Serving Pod
• Create Route when Published: true AND Status.Condition "Installed" to True

(There will be no need to watch the created pod that serves the website since the change of the Tekton Task on the CR will call the reconcile loop)

/cc @rvineetr @dchatzic @kosamara