Fix custom field creation

Bugzilla/Field.pm

@@ -1317,6 +1317,8 @@ sub run_create_validators
         $params->{default_value} = undef;
     }
 
+    $params->{has_activity} = 0;
+
     return $params;
 }
 

editfields.cgi

@@ -57,7 +57,7 @@ elsif ($action eq 'new')
     check_token_data($token, 'add_field');
 
     my $field = $vars->{field} = Bugzilla::Field->create({
-        map { ($_ => $ARGS->{$_}) } Bugzilla::Field->DB_COLUMNS,
+        (map { ($_ => $ARGS->{$_}) } Bugzilla::Field->DB_COLUMNS),
         custom => 1,
         is_mandatory => !$ARGS->{nullable},
     });