maint: add action to check validity of jsonld context #1

	name: Check JSON-LD contexts are valid JSON

	on:
	workflow_dispatch:
	push:
	branches:
	- '**'

	jobs:
	check-context-valid-json:
	runs-on: self-hosted

	steps:
	- name: Checkout repo
	uses: actions/checkout@v4

	- name: Install jq
	run: \|
	sudo apt update && sudo apt install jq

	- name: Check JSON-LD contexts
	run: \|
	cd jsonld-contexts
	for file in $(find . -name "*.jsonld"); do
	printf "Checking $file .. "
	jq empty $file && echo "OK"
	done

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