Resolve #3194494 "Add support for blocking iframes"

Closes #3194494

config/schema/cookieinformation.schema.yml

@@ -10,6 +10,9 @@ cookieinformation.settings:
     enable_google_consent_mode:
       type: boolean
       label: 'Enable Google consent mode'
+    block_iframes:
+      type: boolean
+      label: 'Block iframes unless consent has been given'
     enable_iab:
       type: boolean
       label: 'Enable the IAB cookie consent popup.'