Add value to disable landingPage

[lukma99]

Hello everyone. I am very satisfied with the helm charts, but I have a suggestion.
Currently the landingPage is always deployed with the helm chart. It would be nice to have a flag like landingPage.enabled to turn off creation of the deployment, configmap, service and ingress for the landingPage. I for example have my own frontend to communicate with Theia, so to keep my cluster as clean as possible, I don't want the unused resources.