Update TEST_MAPPING

Test: None

Bug: 233924440
Change-Id: Ic68e1d3316366dcab6c98405546b2dade68aeee4
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 571f133..c6807fc 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -1,5 +1,10 @@
 // Generated by update_crate_tests.py for tests that depend on this crate.
 {
+  "postsubmit": [
+    {
+      "name": "gdbstub_arch_test_src_lib"
+    }
+  ],
   "presubmit": [
     {
       "name": "gdbstub_arch_test_src_lib"