Add B&R on-device unit tests to presubmits

This is a bit of a speculative change. There are a couple unit tests that are
failing (seemingly) only when the whole FrameworksMockingServicesTests
module is run on cloud infra for postsubmits.

Test: Presubmits
Bug: 277732940
Change-Id: I1a3e4a4a71a910dd40e0f1486ee88677af44c652
diff --git a/services/backup/TEST_MAPPING b/services/backup/TEST_MAPPING
index 4a8bd8e..e5395831 100644
--- a/services/backup/TEST_MAPPING
+++ b/services/backup/TEST_MAPPING
@@ -1,6 +1,14 @@
 {
   "presubmit": [
     {
+      "name": "FrameworksMockingServicesTests",
+      "options": [
+        {
+          "include-filter": "com.android.server.backup"
+        }
+      ]
+    },
+    {
       "name": "CtsBackupTestCases"
     }
   ],