Make auth v2 feature flags enabled by default (#6896)

Task/Issue URL:
https://app.asana.com/1/137249556945/project/1205648422731273/task/1211559664717436?focus=true

### Description

In case there is an issue with fetching remote config, we should not
fall back to using Auth v1.

### Steps to test this PR

QA-optional

### No UI changes

Author: lmac012

subscriptions/subscriptions-impl/src/main/java/com/duckduckgo/subscriptions/impl/RealSubscriptions.kt

@@ -192,7 +192,7 @@ interface PrivacyProFeature {
     @Toggle.DefaultValue(DefaultFeatureValue.FALSE)
     fun serpPromoCookie(): Toggle
 
-    @Toggle.DefaultValue(DefaultFeatureValue.FALSE)
+    @Toggle.DefaultValue(DefaultFeatureValue.TRUE)
     fun authApiV2(): Toggle
 
     @Toggle.DefaultValue(DefaultFeatureValue.FALSE)
@@ -227,7 +227,7 @@ interface PrivacyProFeature {
      * This flag will be used to select FE subscription messaging mode.
      * The value is added into GetFeatureConfig to allow FE to select the mode.
      */
-    @Toggle.DefaultValue(DefaultFeatureValue.INTERNAL)
+    @Toggle.DefaultValue(DefaultFeatureValue.TRUE)
     fun enableSubscriptionFlowsV2(): Toggle
 
     /**