fix(cli): add feature flag to control subscription field redaction behavior (#13827)

Author: sundersc

packages/amplify-cli-core/src/feature-flags/featureFlags.ts

@@ -671,6 +671,12 @@ export class FeatureFlags {
         defaultValueForExistingProjects: false,
         defaultValueForNewProjects: true,
       },
+      {
+        name: 'subscriptionsInheritPrimaryAuth',
+        type: 'boolean',
+        defaultValueForExistingProjects: false,
+        defaultValueForNewProjects: false,
+      },
     ]);
 
     this.registerFlag('frontend-ios', [