Return success when disabling a disabled record via REST 2

RT's internal API returns "false" when you update a record
to the value it already has. This false return caused a
REST 2 DELETE (which is 'disable' on most records) to return
failure (500) if you disabled an already-disabled queue.

Detect the "already the current value" message and return true
since the end result, the record being disabled, is true.

Fixes: I#37591

lib/RT/REST2/Resource/Record/DeletableByDisabling.pm

@@ -58,8 +58,16 @@ with 'RT::REST2::Resource::Record::Deletable';
 sub delete_resource {
     my $self = shift;
     my ($ok, $msg) = $self->record->SetDisabled(1);
-    RT->Logger->debug("Failed to disable ", $self->record_class, " #", $self->record->id, ": $msg")
-        unless $ok;
+
+    if ( not $ok && $msg =~ /That is already the current value/ ) {
+        # Don't return failure if the resource is already disabled since
+        # the final state is correct, the resource is disabled.
+        $ok = 1;
+    }
+    else {
+        RT->Logger->debug("Failed to disable ", $self->record_class, " #", $self->record->id, ": $msg");
+    }
+
     return $ok;
 }