Remove TEST_MAPPING.

The test that was in it no longer exists.

Bug: 262624458
Bug: 237249743
Test: presubmit
Change-Id: If9fb58b5f626dac1bd7f737fbaa0cdb4e300bc8e
diff --git a/TEST_MAPPING b/TEST_MAPPING
deleted file mode 100644
index c3321bd..0000000
--- a/TEST_MAPPING
+++ /dev/null
@@ -1,13 +0,0 @@
-// Generated by update_crate_tests.py for tests that depend on this crate.
-{
-  "presubmit": [
-    {
-      "name": "buddy_system_allocator_test_src_lib"
-    }
-  ],
-  "presubmit-rust": [
-    {
-      "name": "buddy_system_allocator_test_src_lib"
-    }
-  ]
-}