Update to /external/robolectric rather than older /external/robolectric-shadows

Bug: 261728063
Test: atest with both robolectric tests.

same failures before/after

Change-Id: Idf0a9073287e98dce70c93910a50946940118305
diff --git a/nearby/tests/robotests/Android.bp b/nearby/tests/robotests/Android.bp
index 56c0107..70fa0c3 100644
--- a/nearby/tests/robotests/Android.bp
+++ b/nearby/tests/robotests/Android.bp
@@ -42,15 +42,14 @@
         "androidx.lifecycle_lifecycle-runtime",
         "androidx.mediarouter_mediarouter-nodeps",
         "error_prone_annotations",
-        "mockito-robolectric-prebuilt",
         "service-nearby-pre-jarjar",
         "truth-prebuilt",
         "robolectric_android-all-stub",
-        "Robolectric_all-target",
     ],
 
     test_options: {
         // timeout in seconds.
         timeout: 36000,
     },
+    upstream: true,
 }