Make tee ignore SIGINT in test-setup.sh

[lixin-wei]

When running bazel run, after ctrl+c, all output will be lost.

The reason is tee is killed by SIGINT before the running binary. All write operation to the pipe after that will fail.

see: https://stackoverflow.com/a/62849155/6191027

In this PR I add -i, --ignore-interrupts option to the tee command to fix this problem.

[fmeum]

@meisterT

[meisterT]

What do you mean with all output will be lost? Is there a minimal example that I can use to repro the behavior?