Create the TEST_MAPPING file

Add FlagMacrosTests in presubmit to ensure that test filtering rule
always work as expected.

Bug: 292707070
Test: atest --test-mapping
Change-Id: I7a08b7e41e95063fb3c188da784f56e0973d4fae

tools/aconfig/TEST_MAPPING

@@ -10,6 +10,12 @@
           "include-filter": "android.cts.flags.tests.FlagAnnotationTest"
         }
       ]
+    },
+    {
+      // Ensure changes on aconfig auto generated library is compatible with
+      // test testing filtering logic. Breakage on this test means all tests
+      // that using the flag macros to do filtering will get affected.
+      "name": "FlagMacrosTests"
     }
   ]
 }