Remove unsafe_ignore_missing_latest_api flag.

API 31 is available now so we can proper api tracking for nearby.

Bug: 189355156
Test: build android
Change-Id: I6e3ce35e7e43fd8b75ef0990796734964ebb1939
diff --git a/nearby/framework/Android.bp b/nearby/framework/Android.bp
index 696f326..5339551 100644
--- a/nearby/framework/Android.bp
+++ b/nearby/framework/Android.bp
@@ -81,5 +81,4 @@
     permitted_packages: [
         "android.nearby",
     ],
-    unsafe_ignore_missing_latest_api: true
 }