Sampling too long Launcher tests

A test that takes > 3 min will generate an artifact file containing stacks of all threads of the test process taken every 3 sec. This artifact will be also generated if the test process is killed, for example, by timeout.

This artifact should help EngProd's effort to speed up presubmits.

Bug: 225186335
Test: local runs
Change-Id: I721779bfbe5bc6289315998ed2660f5f46165611
4 files changed