Android test orchestrator no tests were found

Question

I am developing an Android application using Kotlin programming language. I am writing instrumented tests for my application. I am also using the test orchestrator to run my instrumented tests. But after the installation of the test orchestrator modifying the Grandle file, I cannot run the test in the Android Studio.

I added the following configuration to the app.grandle file

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.2"
    defaultConfig {
        applicationId "com.example.memento"
        minSdkVersion 21
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
//        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        testInstrumentationRunner "com.example.memento.MockTestRunner"
        // Cleared between tests.
        testInstrumentationRunnerArguments clearPackageData: 'true'
        testOptions {
            execution 'ANDROID_TEST_ORCHESTRATOR'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

With this

androidTestImplementation 'com.android.support.test:runner:1.1.1'
    androidTestUtil 'com.android.support.test:orchestrator:1.1.1'

This is the MockTestRunner class

import android.app.Application import android.content.Context import androidx.test.runner.AndroidJUnitRunner import com.example.utils.MockApplicationController

class MockTestRunner: AndroidJUnitRunner()
{
    override fun newApplication(
        cl: ClassLoader?,
        className: String?,
        context: Context?
    ): Application {
        return super.newApplication(cl, MockApplicationController::class.java!!.getName(), context)
    }
}

Then, in the Android Studio, I tried to run a test by right-clicking on the code as follows.

This is what I got when I run the test.

$ adb shell CLASSPATH=$(pm path android.support.test.services) app_process / android.support.test.services.shellexecutor.ShellMain am instrument -r -w -e targetInstrumentation com.example.memento.test/com.example.memento.MockTestRunner   -e debug false -e class 'com.example.memento.EventListTest#eventListIndexZeroTabRendersCurrentEvents' -e clearPackageData true android.support.test.orchestrator/android.support.test.orchestrator.AndroidTestOrchestrator
Waiting for process to come online...

Started running tests
Test running failed: No test results

Literally, not tests were run. What is wrong with my configuration and how can I fix it. If I remove the test orchestrator installation, I can run the tests and it is working as expected.