Bug #43659 MTR2 should report worker data for tests when using --parallel > 1

Adding "w# " before the test result
Also enable --parallel=2 so this can be tested.

mysql-test/collections/default.push

-perl mysql-test-run.pl --timer --force --comment=n_mix --mysqld=--binlog-format=mixed --experimental=collections/default.experimental
-perl mysql-test-run.pl --timer --force --comment=ps_row --ps-protocol --mysqld=--binlog-format=row --experimental=collections/default.experimental
-perl mysql-test-run.pl --timer --force --comment=embedded --embedded --experimental=collections/default.experimental
-perl mysql-test-run.pl --timer --force --comment=rpl_binlog_row --suite=rpl,binlog --mysqld=--binlog-format=row --experimental=collections/default.experimental
-perl mysql-test-run.pl --timer --force --comment=funcs_1 --suite=funcs_1 --experimental=collections/default.experimental
+perl mysql-test-run.pl --timer --force --parallel=2 --comment=n_mix --mysqld=--binlog-format=mixed --experimental=collections/default.experimental
+perl mysql-test-run.pl --timer --force --parallel=2 --comment=ps_row --ps-protocol --mysqld=--binlog-format=row --experimental=collections/default.experimental
+perl mysql-test-run.pl --timer --force --parallel=2 --comment=embedded --embedded --experimental=collections/default.experimental
+perl mysql-test-run.pl --timer --force --parallel=2 --comment=rpl_binlog_row --suite=rpl,binlog --mysqld=--binlog-format=row --experimental=collections/default.experimental
+perl mysql-test-run.pl --timer --force --parallel=2 --comment=funcs_1 --suite=funcs_1 --experimental=collections/default.experimental

mysql-test/lib/mtr_report.pm

@@ -71,6 +71,8 @@ sub _mtr_report_test_name ($) {
 
   print _name(), _timestamp();
   printf "%-40s ", $tname;
+  my $worker = $tinfo->{worker};
+  printf "w$worker " if $worker;
 
   return $tname;
 }

mysql-test/mysql-test-run.pl

@@ -723,6 +723,8 @@ sub run_worker ($) {
       delete($test->{'comment'});
       delete($test->{'logfile'});
 
+      $test->{worker} = $thread_num if $opt_parallel > 1;
+
       run_testcase($test);
       #$test->{result}= 'MTR_RES_PASSED';
       # Send it back, now with results set