Added dormant private feature flag for drip sequences (#27054)

closes https://linear.app/ghost/issue/NY-1187

This change should have no user impact.

Author: EvanHahn

apps/admin-x-settings/src/components/settings/advanced/labs/private-features.tsx

@@ -51,6 +51,10 @@ const features: Feature[] = [{
     title: 'Members Forward',
     description: 'Use the new React-based members list instead of the Ember implementation',
     flag: 'membersForward'
+}, {
+    title: 'Drip Sequences',
+    description: 'Enable welcome email drip sequences',
+    flag: 'dripSequences'
 }, {
     title: 'Welcome Emails Design Customization',
     description: 'Enable design customization options for welcome emails',

ghost/core/core/shared/labs.js

@@ -48,6 +48,7 @@ const PRIVATE_FEATURES = [
     'themeTranslation',
     'indexnow',
     'membersForward',
+    'dripSequences',
     'welcomeEmailsDesignCustomization',
     'pictureImageFormats',
     'smarterCounts',

ghost/core/test/e2e-api/admin/__snapshots__/config.test.js.snap

@@ -12,6 +12,7 @@ Object {
       "additionalPaymentMethods": true,
       "commentModeration": true,
       "customFonts": true,
+      "dripSequences": true,
       "editorExcerpt": true,
       "emailCustomization": true,
       "emailUniqueid": true,