Add hidl_test to TEST_MAPPING

There are dependencies that are tested, so make sure they run in
presubmits.

Test: atest hidl_test
Bug: 319502861
Change-Id: I4bc4c1d02bc9c72498575f1b98567984011364a3
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 6f3bcea..4e330d8 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -20,6 +20,9 @@
     },
     {
       "name": "vts_treble_vintf_vendor_test"
+    },
+    {
+      "name": "hidl_test"
     }
   ]
 }