Promote CtsOsTestCases to presubmits

Now that they have soaked in postsubmits we can promote the tests to run
in presubmits.

Test: none
Bug: 333079136
Change-Id: Ia617d36d4aea34ade65639a4925cd3083e824317
diff --git a/TEST_MAPPING b/TEST_MAPPING
index a9ce2a2..7193d26 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -23,9 +23,7 @@
     },
     {
       "name": "hidl_test"
-    }
-  ],
-  "postsubmit": [
+    },
     {
        "name": "CtsOsTestCases",
        "options": [