Mark liblatinime_unittests as unit_test:true to run in presubmit in CI

This will ensure that the target stays green.
Note: we will clean up the explicit unit_tests:true once cc_test default is changed.

Change-Id: I5153ca918e94b370b1f08289118877d209385ba2
Test: presubmit
Bug: 180014759
diff --git a/native/jni/Android.bp b/native/jni/Android.bp
index 7419ed1..b522cb3 100644
--- a/native/jni/Android.bp
+++ b/native/jni/Android.bp
@@ -179,7 +179,9 @@
 cc_test {
     name: "liblatinime_unittests",
     host_supported: true,
-
+    test_options: {
+        unit_test: true,
+    },
     cflags: [
         "-Wno-unused-parameter",
         "-Wno-unused-function",