Getting error on using classes from kotlinx-coroutine-test

Change your library version to 1.3.2 instead of 1.3.0-M1 like so:

testImplementation 'org.jetbrains.kotlinx:kotlinx-coroutines-test:1.3.2'

And be sure that your tests are unit test in the test folder, not instrumented test in androidTest folder.

replacing testImplementation with implementation did the trick for me.