Add check for definition xrefs that are not also term xrefs #1452

	# This is a basic workflow to help you get started with Actions

	name: CI

	# Controls when the action will run.
	on:
	# Triggers the workflow on push or pull request events but only for the master branch
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	# Allows you to run this workflow manually from the Actions tab
	workflow_dispatch:

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	validate_yaml_and_metadata:
	runs-on: ubuntu-latest
	container: geneontology/dev-base:latest
	steps:
	- uses: actions/checkout@v2
	- name: Install packages
	run: apt-get update -qq && apt-get install -y python3 python3-pip mmv -qq
	- name: Install python stuff
	run: pip3 install pyyaml typing linkml==1.7.4
	## Validate YAML schema for https://github.com/geneontology/go-ontology/issues/27399
	- name: Validate YAML schema
	run: \|
	linkml-validate -s src/ontology/subsets/subsets.schema.yaml src/ontology/subsets/go_subsets_metadata.yaml

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