fix: add missing defaultdict import in schema validation #3

	name: "validate-pr"

	on:
	pull_request:

	permissions:
	contents: "read"

	concurrency:
	group: "validate-pr-${{ github.event.pull_request.number \|\| github.run_id }}"
	cancel-in-progress: true

	defaults:
	run:
	shell: "bash -euxo pipefail {0}"

	env:
	PYTHONUNBUFFERED: "1"

	jobs:
	validate:
	runs-on: "ubuntu-24.04"

	steps:
	- name: "Checkout PR code"
	uses: "actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683" # v4.2.2
	with:
	repository: "${{ github.event.pull_request.head.repo.full_name }}"
	ref: "${{ github.event.pull_request.head.ref }}"
	fetch-depth: 0
	fetch-tags: true

	- name: "Install system dependencies"
	run: "sudo apt-get install genometools python3 --yes -qq >/dev/null"

	- name: "Install Python dependencies"
	run: "pip3 install -r requirements.txt"

	- name: "Validate GFF files"
	run: "./scripts/validate-gff 'data/'"

	- name: "Rebuild (validation only)"
	id: "rebuild"
	continue-on-error: true
	run: "./scripts/rebuild --input-dir 'data/' --output-dir 'data_output/' --no-pull --allow-dirty"

	- name: "Upload validation artifacts"
	if: "always()"
	uses: "actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02" # v4.6.2
	with:
	name: "validation-output"
	path: "data_output/"

	- name: "Fail if rebuild or validation found errors"
	if: "steps.rebuild.outcome == 'failure'"
	run: "exit 1"

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