Update TEST_MAPPING

Test: None

Bug: 233924440
Change-Id: I1ebb20241a2e3534265e298ad4e2770f612b3c8b
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 161921c..6a0ccd2 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -17,6 +17,11 @@
       "path": "external/rust/crates/unicode-xid"
     }
   ],
+  "postsubmit": [
+    {
+      "name": "crossbeam-epoch_test_src_lib"
+    }
+  ],
   "presubmit": [
     {
       "name": "crossbeam-epoch_test_src_lib"