Fix recent settings migrations (#36602)

db/migrate/20251002140103_migrate_timeline_preview_setting.rb

@@ -12,8 +12,7 @@ class MigrateTimelinePreviewSetting < ActiveRecord::Migration[8.0]
     Setting.upsert_all(
       %w(local_live_feed_access remote_live_feed_access local_topic_feed_access remote_topic_feed_access).map do |var|
         { var: var, value: value ? "--- public\n" : "--- authenticated\n" }
-      end,
-      unique_by: :var
+      end
     )
   end
 

db/migrate/20251023210145_migrate_landing_page_setting.rb

@@ -9,10 +9,10 @@ class MigrateLandingPageSetting < ActiveRecord::Migration[8.0]
 
     value = YAML.safe_load(setting.attributes['value'], permitted_classes: [ActiveSupport::HashWithIndifferentAccess, Symbol])
 
-    Setting.upsert(
+    Setting.upsert({
       var: 'landing_page',
-      value: value ? "--- trends\n" : "--- about\n"
-    )
+      value: value ? "--- trends\n" : "--- about\n",
+    })
   end
 
   def down; end