We are following below docuement to run child pipeline in scale parallel steps.
Advanced Workflows with Parallel steps · Codefresh | Docs. Below is the sample code.
upgrade_pipeline version:
  type: freestyle
  stage: update
  arguments:
    PIPELINE_ID: 'blueprints/multi-repo-upgrader tool'
	  environment: 
	    - 'CF_REPO_OWNER="Github_Org"'
	    - 'CF_COMMIT_AUTHOR=$CF_COMMIT_AUTHOR'
	    - 'CF_COMMIT_MESSAGE=$CF_COMMIT_MESSAGE'
	    - 'SKIP_APPROVAL=true'
	    - 'DRYRUN_ONLY=${{DRYRUN_ONLY}}'
	    - 'BRANCH="test"'
	  scale:
	    upgrade-multi-repo-upgrader:
		  title: Upgrade pipeline version of Repo1
		  environment:
		    - 'CF_REPO_NAME="XXXXXXX"'
	    upgrade-hscmanishjainctr:
		  title: Upgrade pipeline version of Repo2
		  environment:
		    - 'CF_REPO_NAME="XXXXXXX"' 
Its giving me below error
####################################
Running plugin upgrade_pipeline version
Failed to prepare plugin. Validation error
should NOT have additional properties
keyword:additionalProperties
schema path: #/additionalProperties
params:
additionalProperty:scale
[SYSTEM]
Message             Validation error
Documentation Link  Steps · Codefresh | Docs
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