Synchronize checkTrace to allow parallel SimulationWorkers to use non-thread-safe LiveCheck1.
Synchronize checkTrace to allow parallel SimulationWorkers to use
non-thread-safe LiveCheck1.

https://github.com/tlaplus/tlaplus/pull/210

[Bug][TLC]
tlaplus/tlaplus,lemmy/tlaplus,lemmy/tlaplus,tlaplus/tlaplus,lemmy/tlaplus,lemmy/tlaplus,tlaplus/tlaplus,tlaplus/tlaplus