Switch to bionic gtest in bootable/recovery

We encountered segfaults in Imgdiff host tests due to the failure to
reset states of getopt. The problem can be solved by switching to use
bionic's gtest where a new process is forked for each test.

Also modify the recovery_component_test to make sure it runs in parallel.
Changes include:
  1. Merge the writes to misc partition into one single test.
  2. Change the hard coded location "/cache/saved.file" into a configurable
  variable.

Bug: 67849209
Test: recovery tests pass

Change-Id: I165d313f32b83393fb7922c5078636ac40b50bc2