Fix test for FSRS default enabled

Update deckconfig::update::test::updating to use actual config values from get_deck_configs_for_update() instead of hardcoded values. This ensures the test works correctly now that FSRS is enabled by default.

rslib/src/deckconfig/update.rs

@@ -501,7 +501,7 @@ mod test {
             limits: Limits::default(),
             new_cards_ignore_review_limit: false,
             apply_all_parent_limits: false,
-            fsrs: false,
+            fsrs: true,
             fsrs_reschedule: false,
             fsrs_health_check: true,
         };