Azure DevOps SSIS Build task doesn't produce dtsconfig file

I have 3 dtsx packages (package deployment model) that are now being locally built in VisualStudio 2019 .

This process produces the 3 files inside the bin/deployment folder,(.deploymentManifest, .dtsx and .dtsconfig) , needed to install and configure the job steps :

The pipeline job builds it in a similar way using nuget and SSIS Build task.

https://i.stack.imgur.com/fO2AQ.png

https://i.stack.imgur.com/fO2AQ.png

But doesn’t produce the dtsconfig file

https://i.stack.imgur.com/94ARB.png

I've tried using environment variables in package configuration with the same result. 

I’ve tried using relative path and copying the dtsconfig into the folder but the deploymentManifest file just don’t have the ConfigurationFile tag.

<?xml version="1.0" encoding="UTF-8"?>
<DTSDeploymentManifest GeneratedBy="WIN-1V2BO1VIS10\VssAdministrator" GeneratedFromProjectName="ETL"
 GeneratedDate="2021-10-14T16:21:19.2937202+00:00" AllowConfigurationChanges="true"> 
<Package>Populate_DW_XX.dtsx
</Package> 
</DTSDeploymentManifest>