Fix set union error in `_propagate_shared_texts` #784

	name: pyre

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	workflow_dispatch:

	jobs:
	pyre:
	runs-on: ubuntu-20.04
	strategy:
	matrix:
	python-version: ["3.8", "3.9", "3.10", "3.11"]

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}

	- name: Install Dependencies
	run: \|
	python -m pip install --upgrade pip
	python -m pip install -r requirements.txt
	python -m pip install cython
	python -m pip install graphql-core typing_inspect
	VERSION=$(grep "version" .pyre_configuration \| sed -n -e 's/.$0\.0\.[0-9]$.*/\1/p')
	python -m pip install pyre-check-nightly==$VERSION

	- name: Run Pyre
	run: \|
	pyre check

Provide feedback