Remove iterator feature flag (#15165)

As title

packages/twenty-server/src/engine/core-modules/feature-flag/constants/public-feature-flag.const.ts

@@ -31,15 +31,6 @@ export const PUBLIC_FEATURE_FLAGS: PublicFeatureFlag[] = [
         'https://twenty.com/images/lab/is-message-folder-control-enabled.png',
     },
   },
-  {
-    key: FeatureFlagKey.IS_WORKFLOW_ITERATOR_ENABLED,
-    metadata: {
-      label: 'Workflow Iterator',
-      description: 'Iterate over a list of items in a workflow',
-      imagePath:
-        'https://twenty.com/images/lab/is-workflow-iterator-enabled.png',
-    },
-  },
   {
     key: FeatureFlagKey.IS_CALENDAR_VIEW_ENABLED,
     metadata: {

packages/twenty-server/src/engine/core-modules/feature-flag/enums/feature-flag-key.enum.ts

@@ -15,7 +15,6 @@ export enum FeatureFlagKey {
   IS_PAGE_LAYOUT_ENABLED = 'IS_PAGE_LAYOUT_ENABLED',
   IS_RECORD_PAGE_LAYOUT_ENABLED = 'IS_RECORD_PAGE_LAYOUT_ENABLED',
   IS_MESSAGE_FOLDER_CONTROL_ENABLED = 'IS_MESSAGE_FOLDER_CONTROL_ENABLED',
-  IS_WORKFLOW_ITERATOR_ENABLED = 'IS_WORKFLOW_ITERATOR_ENABLED',
   IS_CALENDAR_VIEW_ENABLED = 'IS_CALENDAR_VIEW_ENABLED',
   IS_GROUP_BY_ENABLED = 'IS_GROUP_BY_ENABLED',
   IS_PUBLIC_DOMAIN_ENABLED = 'IS_PUBLIC_DOMAIN_ENABLED',