MDEV-39831 mtr: under rr use LSAN_OPTIONS=report_objects

When we have a rr recording of the process, a memory location
is a useful thing to have in the err log of leaks.

The output comes out like:

Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x55b08dbccdb8 in malloc (/build/sql/mariadbd+0x1b89db8) (BuildId: 4d72569bed63ce1fbf55d51e4d4a84b610efd87d)
    #1 0x7b3fe387a1b1  (<unknown module>)
    #2 0x7b3fe37c492f  (<unknown module>)
    #3 0x7b3fe3058407  (<unknown module>)
    #4 0x7b3fe2f09493  (<unknown module>)

Objects leaked above:
0x7b7feafe0990 (40 bytes)

Now once the location is resolved we can check that we resolving the
right object leak.

Author: grooverdan

mysql-test/lib/My/Debugger.pm

@@ -84,6 +84,7 @@ my %debuggers = (
       push @::global_suppressions, qr/InnoDB: native AIO failed/;
       ::mtr_error('rr requires kernel.perf_event_paranoid <= 1')
         if ::mtr_grab_file('/proc/sys/kernel/perf_event_paranoid') > 1;
+      $ENV{LSAN_OPTIONS}= "report_objects=1:" . ($ENV{LSAN_OPTIONS} || '');
     }
   },
   valgdb => {