Clean up rust_test_host TEST_MAPPING after default update am: 46f8277855 am: 575e0b68f5 am: 30b2eee2f7 am: 420d692816

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/fallible-iterator/+/1589993

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I8d4db24efe83e41ee923c9262949d6e2872e8cba
diff --git a/TEST_MAPPING b/TEST_MAPPING
index f31bdbb..27759f0 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -2,10 +2,6 @@
 {
   "presubmit": [
     {
-      "host": true,
-      "name": "fallible-iterator_host_test_src_lib"
-    },
-    {
       "name": "fallible-iterator_device_test_src_lib"
     }
   ]