perf test perf-report-hierarchy: Add new test

perf test perf-report-hierarchy: Add new test

Super simple test to check that at least we're not segfaulting when
trying to use 'perf report --hierarchy', more subtests should be added
to make sure the output is the expected one.

This is being merged right before a fix for that that this test detects:

  # perf test hierarchy
   83: perf report --hierarchy                                         : FAILED!
  # perf test -v hierarchy
  --- start ---
  test child forked, pid 102242
  perf report --hierarchy
  Linux
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.025 MB /tmp/perf-test-report.HX0N85TlPq/perf-report-hierarchy-perf.data (6 samples) ]
  perf: ui/hist.c:603: fmt_free: Assertion `!(!list_empty(&fmt->sort_list))' failed.
  /home/acme/libexec/perf-core/tests/shell/perf-report-hierarchy.sh: line 34: 102250 Aborted                 (core dumped) perf report --hierarchy > /dev/null
  --- Cleaning up ---
  ---- end(-1) ----
   83: perf report --hierarchy                                         : FAILED!
  #

Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/lkml/20250430180321.736939-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>