[ci] enable second_deadlock_stack for TSan

Summary: this gives us more informative error logs when TSan detects a lock inversion

Test Plan:
invert a LOCK2(...) in a test somewhere

CC=clang CXX=clang++ cmake .. -GNinja -DENABLE_SANITIZERS=thread
ninja all check

make sure the TSan warning output is more informative

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D9090