Add custom response header
gcloud beta compute backend-services update seongland-account --global \ --custom-response-header X-Frame-Options:DENY \ --custom-response-header X-XSS-Protection:1 \ --custom-response-header X-Content-Type-Options:nosniff
Remove all header
gcloud beta compute backend-services update seongland-account \ --global \ --no-custom-request-headers