Fix flaky signal handler test on mono on Linux#125969

Merged

mrek-msft merged 2 commits intodotnet:mainfrom

mrek-msft:dev/mrek/meh-sigquit-mono-fail

Mar 24, 2026

Commits on Mar 23, 2026

Fix flaky test caused by non-empty stdout check when remote process is faster then test process.
mrek-msft
committed
Rework to do not send two signal in Mono case.
mrek-msft
committed