Delete duplicated last_age var

Check.pm

@@ -141,7 +141,6 @@ sub action
       my $age = -1;
       $check = {
         bkp             => 0,
-        last_age        => 0,
         errors          => 0,
         new_size        => 0,
         new_size_avg    => 0,
@@ -173,7 +172,6 @@ sub action
         $check->{new_size_q1}      = eval { int $sizes->quantile(1) } || 0;
         $check->{new_size_q3}      = eval { int $sizes->quantile(3) } || 0;
         $check->{age}              = time - $bpc_info[$i]->{startTime};
-        $check->{last_age}         = sprintf("%.1f", ($check->{age}) / 84600);
       }
 
       # TOO BIG ?