perf tests shell task_analyzer: Run this test exclusively

perf tests shell task_analyzer: Run this test exclusively

When running in the now default parallel mode this test has been
frequently failing, while when running exclusively, on a quiet system,
it passes.

Since its expectations were established when serial testing was the
norm, mark it as exclusive to get this kind of resunt:

  root@x1:~# perf test 106
  106: perf script task-analyzer tests                                 : Ok
  root@x1:~# set -o vi
  root@x1:~# perf stat --null --repeat 10 perf test 106
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok
  106: perf script task-analyzer tests                                 : Ok

   Performance counter stats for 'perf test 106' (10 runs):

              4.8872 +- 0.0179 seconds time elapsed  ( +-  0.37% )

  root@x1:~#

Cc: Aditya Gupta <adityag@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com
Cc: James Clark <james.clark@linaro.org>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>