perf test: Add CSV summary test

The patch "perf stat: Align CSV output for summary mode" aligned CSV
output and added "summary" to the first column of summary lines.

Now we check if the "summary" string is added to the CSV output.

If we set '--no-csv-summary' option, the "summary" string would not be
added, also check with this case.

Committer testing:

  $ perf test csv
  84: perf stat csv summary test     : Ok
  $

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210319070156.20394-2-yao.jin@linux.intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>