tests/core/cond_order/: calling cond signal and broadcast without waiting threads

[JulianHolzwarth]

Contribution description

Through test coverage, I noticed the test never tried the functions cond_signal and cond_broadcast without a thread waiting. This change helps to find problems with the functions when no thread is waiting.

Testing procedure

BOARD=native make -C tests/core/cond_order flash test
check test coverage before and after (I used simple coverage of thread communication)

[riot-ci]

Murdock results

✔️ PASSED

1ed2f36 tests/cond_order/main.c: testing without waiting threads

Success	Failures	Total	Runtime
22	0	23	01m:44s

Artifacts

• Documentation preview

[mguetschow]

Thanks, LGTM! I'll trust CI for testing.

[maribu]

I toggled the merge queue to prevent a timeout. The nightly build is still in front of this PR, but is done in about 2h. So this should pass now before the 360 min timeout is hit.