perf tests: Add test for trace output loss

perf tests: Add test for trace output loss

Add a test that checks that trace output is not lost to races. This is
accomplished by tracing the exit_group syscall of "true" multiple times and
checking for correct output.

Signed-off-by: Benjamin Peterson <benjamin@engflow.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Howard Chu <howardchu95@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20241107232128.108981-3-benjamin@engflow.com
[ Addressed two ShellCheck warnings ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>