Update TEST_MAPPING

Test: None

Bug: 233924440
Change-Id: Icab63d07c76e38ff0d1d47a67bb8bad8029a8066
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 470b30a..c8acf3b 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -11,6 +11,11 @@
       "path": "external/rust/crates/regex"
     }
   ],
+  "postsubmit": [
+    {
+      "name": "quickcheck_test_src_lib"
+    }
+  ],
   "presubmit": [
     {
       "name": "quickcheck_test_src_lib"