media.c2 aidl: Add a test for GraphicsTracker

Add a test for GraphicsTracker. The test will verify the basic
assumptions and functional correctness of GraphicsTracker
implementation.

Test: m
Bug: 254050314
Change-Id: I0b937f6657aa373f5cf30137f140606a29105e79
diff --git a/media/codec2/TEST_MAPPING b/media/codec2/TEST_MAPPING
index 8a894f3..b911e11 100644
--- a/media/codec2/TEST_MAPPING
+++ b/media/codec2/TEST_MAPPING
@@ -25,5 +25,8 @@
         }
       ]
     }
+  ],
+  "postsubmit": [
+    { "name": "c2aidl_gtracker_test"}
   ]
 }