[Apple] Fix job re-runs by emitting stripped assemblies to separate directory

[kotlarmilos]

Problem

On second and all subsequent attempts to run Apple mobile job on Helix, the trimmer or ilstrip output the assemblies to the same directory as the input. As a result, on the second and all subsequent runs, the input assemblies are already stripped, causing the Invalid IL code in SimpleTestRunner:Main (string[]): IL_0000: ret.

Output assemblies should be emitted to a different directory to ensure subsequent runs can execute without errors.

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