Getting "The test APK does not contain the test runner class specified by the user or the manifest file." with Firebase

I am getting the following error trying to run UI tests on firebase through commandline:

Test [matrix-1dy3j2omlw7n9] has been created in the Google Cloud.
Firebase Test Lab will execute your instrumentation test on 1 device(s).
Creating individual test executions...failed.                                  
ERROR: (gcloud.firebase.test.android.run) 
Matrix [matrix-1dy3j2omlw7n9] failed during validation: The test APK does not contain the test runner class specified by the user or the manifest file. The test runner class name may be incorrect, or the class may be mislocated in the app APK..

When I try to run the test through command line locally with the 2 apks, I am able to run the test just fine. This is what I using in command line to get the error message from firebase:

gcloud firebase test android run \
>   --type instrumentation \
>   --app app-fred-stage-debug-androidTest.apk \
>   --test app-fred-stage-debug.apk \
>   --device model=Nexus6,version=21,locale=en,orientation=portrait

What do I need to add to fix this and where?

TIA