ActivityTestRule Class deprecated

[Zardozz]

• [X] I have searched existing issues and confirmed this is not a duplicate

Issues and steps to reproduce

ActivityTestRule Class used in the Android Integration tests is deprecated
See
https://developer.android.com/reference/androidx/test/rule/package-summary

Change the androidxTestVersion to "1.3.0" in the library buld.gradle and "ActivityTestRule" used in most of the library Integration (AndroidTest) tests shows up as deprecated (but still currently works)

Expected behavior

Not to use deprecated classes

Version of the flexbox library

• 2.0.1