Clean up rust_test_host TEST_MAPPING after default update am: 7b41568a63 am: ad02e9381d

Original change: https://android-review.googlesource.com/c/platform/external/libchromeos-rs/+/1582586

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ie16fc88e44b7dffa873e10064bc1d48e8c082368
diff --git a/TEST_MAPPING b/TEST_MAPPING
deleted file mode 100644
index 9882312..0000000
--- a/TEST_MAPPING
+++ /dev/null
@@ -1,13 +0,0 @@
-// Generated by cargo2android.py for tests in Android.bp
-{
-  "presubmit": [
-    {
-      "host": true,
-      "name": "libchromeos-rs_host_test_src_lib"
-// Presubmit tries to run x86, but we only support 64-bit builds.
-//    },
-//    {
-//      "name": "libchromeos-rs_device_test_src_lib"
-    }
-  ]
-}