Bump rexml from 3.3.6 to 3.3.9 #143

	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: cti-documentation test harness
	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-latest

	name: Python 3.x Build
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python 3.x
	uses: actions/setup-python@v2
	with:
	python-version: '3.x'
	- name: Install and update essential dependencies
	run: \|
	pip install -U pip setuptools
	pip install stix2-validator
	- name: Validate Examples
	run: \|
	./validate-examples.sh

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