Clean up rust_test_host TEST_MAPPING after default update am: 6be6a10d6d

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/proc-macro-nested/+/1584272

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ia0125d4ad0f39ef5aceb69b000e66c1c07ad618f
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 68b0dec..0cba459 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -2,17 +2,9 @@
 {
   "presubmit": [
     {
-      "host": true,
-      "name": "proc-macro-nested_host_test_src_lib"
-    },
-    {
       "name": "proc-macro-nested_device_test_src_lib"
     },
     {
-      "host": true,
-      "name": "futures-util_host_test_src_lib"
-    },
-    {
       "name": "futures-util_device_test_src_lib"
     }
   ]