Fix part of #2480: Work around for espresso tests in ExplorationActivityTest

[srikanthkb]

Explanation

Fixes part of #2480 :

This PR is a work-around for the test testAudioWithWifi_openRatioExploration_clickAudioIcon_checkAudioFragmentHasDefaultLanguageAndAutoPlays() in ExplorationActivityTest to be successful on Espresso.
More detailed investigation is required on how testCoroutineDispatchers.unregisterIdleResource() allows this test to pass on Espresso.

Checklist

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[anandwana001]

@Srikanth-Kb PTAL
https://gist.github.com/anandwana001/fa497cb8981606313c9dc3a8a26fcdb3

[srikanthkb]

@Srikanth-Kb PTAL
https://gist.github.com/anandwana001/fa497cb8981606313c9dc3a8a26fcdb3

This is passing successfully for each run that I made locally. But, I am not sure how safe testCoroutineDispatchers.registerIdlingResource() is for these tests. Also, there is no guarantee that this will work 100% of the runs. Should we maybe get Ben's opinion on this ?

[anandwana001]

We will be deferring to Ben, once we are able to pass the test on both Espresso and Robolectric. I will be trying more on this week and update here.

[anandwana001]

Closing this PR