Add examples to testability guidelines
Add examples to testability guidelines

PiperOrigin-RevId: 454599460
Change-Id: I275c3aec061c7462018f10db4dec4d0b01484ee3

AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx