Use suitable assert

Replace assertTrue(a in b) with assertIn(a, b)
Replace assertTrue(a in [b, c]) with assertIn(a, [b, c])
Replace assertTrue(a is None) with assertIsNone(a)
Replace assertTrue(a == b) with assertEqual(a, b)
Replace assertFalse(a == b) with assertNotEqual(a, b)

Change-Id: I10c3abce14953b97568a5ce9d45f63af22d71ac3
Merge "Use suitable assert"