tests: Remove obsolete classes in applypatch_test.

ApplyPatchFullTest and ApplyPatchDoubleCacheTest were used for defining
testcases for file-based OTA. The testcases have already been removed by
commit 40e144da. This CL removes the
obsolete class defnitions.

Bug: 37559618
Test: recovery_component_test on angler and marlin respectively.
Change-Id: I3f4f1dfc8580cf010365e671de256f68bbc0d99a