Avoid mocking the Process class in DexUseManagerTest.

Process is a class on bootclasspath, so the test framework may use it as
well. If we mock it, we affect the test framework, causing unexpected
behaviors.

Bug: 397234253
Bug: 397561164
Change-Id: I94f8b46b272374904b8ffbba46ebd30e4ea75019
Test: Presubmit
2 files changed