Fix json format in expectations file

Test: vogar --mode=host --expectations \
      art/tools/libcore_gcstress_debug_failures.txt -- jsr166
Change-Id: I60656f0678341d4d4a4e0b2977352d18208b303b
diff --git a/tools/libcore_gcstress_debug_failures.txt b/tools/libcore_gcstress_debug_failures.txt
index d56c341..e8f3e1f 100644
--- a/tools/libcore_gcstress_debug_failures.txt
+++ b/tools/libcore_gcstress_debug_failures.txt
@@ -51,7 +51,7 @@
           "org.apache.harmony.tests.java.lang.ref.ReferenceQueueTest#test_removeJ",
           "org.apache.harmony.tests.java.lang.ProcessManagerTest#testSleep",
           "org.apache.harmony.tests.java.util.TimerTest#testOverdueTaskExecutesImmediately",
-          "org.apache.harmony.tests.java.util.WeakHashMapTest#test_keySet_hasNext",
+          "org.apache.harmony.tests.java.util.WeakHashMapTest#test_keySet_hasNext"
   ]
 },
 {
@@ -81,6 +81,7 @@
           "test.java.lang.StrictMath.HypotTests_testAgainstTranslit_shard3",
           "test.java.lang.StrictMath.HypotTests_testAgainstTranslit_shard4",
           "test.java.math.BigDecimal",
-          "test.java.math.BigInteger_testConstructor"]
+          "test.java.math.BigInteger_testConstructor"
+  ]
 }
 ]