Move apex_rollback_tests to group presubmit-large

The test config takes longer than 15mins to run. Move it to a dedicated
group for running slow presubmit Test Mapping tests.

Bug: 174654670
Bug: 174495337
Bug: 175150979

Change-Id: Ie1a002551f400584ad8f2ffdfce0ff2bf2383760
Test: None
diff --git a/tests/TEST_MAPPING b/tests/TEST_MAPPING
index 9e3a0a3..81580ce 100644
--- a/tests/TEST_MAPPING
+++ b/tests/TEST_MAPPING
@@ -1,9 +1,6 @@
 {
   "presubmit": [
     {
-      "name": "apex_rollback_tests"
-    },
-    {
       "name": "apex_targetprep_tests"
     },
     {
@@ -15,6 +12,9 @@
   ],
   "presubmit-large": [
     {
+      "name": "apex_rollback_tests"
+    },
+    {
       "name": "sharedlibs_host_tests"
     }
   ],