OZG-7324: Also remove Helm Charts for backend

src/main/helm/.helmignore

src/main/helm/Chart.yaml

src/main/helm/templates/_helpers.tpl

src/main/helm/templates/bindings_type_configmap.yaml

src/main/helm/templates/deployment.yaml

src/main/helm/templates/ingress.yaml

src/main/helm/templates/keycloak_client_crd.yaml

src/main/helm/templates/keycloak_crd.yaml

src/main/helm/templates/keycloak_group_crd.yaml

src/main/helm/templates/keycloak_user_crd.yaml

src/main/helm/templates/network_policy.yaml

...mplates/ozgcloud_keycloak_operator_secrets_read_role.yaml

...ozgcloud_keycloak_operator_secrets_read_role_binding.yaml

...plates/ozgcloud_keycloak_operator_secrets_write_role.yaml

...zgcloud_keycloak_operator_secrets_write_role_binding.yaml

src/main/helm/templates/service.yaml

src/main/helm/templates/service_account.yaml

src/main/helm/templates/service_monitor.yaml

src/main/helm/templates/tests/test-ingress-connection.yaml

src/main/helm/templates/tests/test-service-connection.yaml