Fix instance sets

By mistake, the instance sets for the plasp planner configuration were
incorrect.

configurations.yml

@@ -70,4 +70,4 @@ configurations:
   instanceSets: ["rintanen-aij-2012-interesting"]
 - id: "gc-ta1-tt1"
   options: [*basics, *fastDownwardPreprocessing, *plannerB, *encoding0, *shallow, *heuristics, *generateAndCheck, *testAdd1, *testTimes1]
-  instanceSets: ["lpnmr-easy-instances", "lpnmr-hard-instances", "lpnmr-first-plan-not-serializable", "rintanen-aij-2012"]
+  instanceSets: ["rintanen-aij-2012-interesting"]