Description of problem:

Configuration of executor_thread_pool_size is failing with duplicate declaration since this param is moved to oslo messaging but we do not see it in puppet-heat.

+++
ControllerExtraConfig:
    heat::config::heat_config:
      DEFAULT/executor_thread_pool_size:
        value:  24

With the same config, this fails in RHOSP16.2 with the following error on the controllers:

        Feb 28 15:10:22 ctrl0 puppet-user[501416]: Error: Evaluation Error: Error while evaluating a Resource Statement, Evaluation Error: Error while evaluating a Function Call, Duplicate declaration: Heat_config[DEFAULT/executor_thread_pool_size] is already declared at (file: /etc/puppet/modules/heat/manifests/config.pp, line: 36); cannot redeclare (file: /etc/puppet/modules/oslo/manifests/messaging/default.pp, line: 47) (file: /etc/puppet/modules/oslo/manifests/messaging/default.pp, line: 47, column: 3) (file: /etc/puppet/modules/heat/manifests/init.pp, line: 445) on node 
+++
Param in oslo
+++
define oslo::messaging::default(
  $executor_thread_pool_size = $::os_service_default,
  $rpc_response_timeout      = $::os_service_default,
  $transport_url             = $::os_service_default,
  $control_exchange          = $::os_service_default,
) {

  $default_options = {
    'DEFAULT/executor_thread_pool_size' => { value => $executor_thread_pool_size }, <<<<<<<<<<<
    'DEFAULT/rpc_response_timeout'      => { value => $rpc_response_timeout },
    'DEFAULT/transport_url'             => { value => $transport_url, secret => true },
    'DEFAULT/control_exchange'          => { value => $control_exchange },
+++

Recently upstream patch was filed & we are looking if it's possible to backport it to OSP16.
https://review.opendev.org/c/openstack/puppet-heat/+/876489

Version-Release number of selected component (if applicable):
16.2

How reproducible:
Everytime

Steps to Reproduce:
1.
2.
3.

Actual results:
Not able to config param

Expected results:
Should be able to config.

Additional info: