Update TEST_MAPPING am: 76d5338c

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/unicode-width/+/2006199

Change-Id: Ic39ac44cb046cc8840dbe190d0c6156895892f56

TEST_MAPPING

 // Generated by update_crate_tests.py for tests that depend on this crate.
 {
   "presubmit": [
+    {
+      "name": "diced_test"
+    },
     {
       "name": "keystore2_test"
     },
@@ -15,6 +18,9 @@
     }
   ],
   "presubmit-rust": [
+    {
+      "name": "diced_test"
+    },
     {
       "name": "keystore2_test"
     },