Add rough cut of 'blobbase' #565

	name: Run tests

	on: [push, pull_request]

	jobs:
	run-tests:
	strategy:
	matrix:
	os: [ 'windows', 'ubuntu', 'macos' ]
	fail-fast: false
	runs-on: ${{ matrix.os }}-latest
	steps:
	- uses: actions/checkout@v4
	- name: Setup python
	uses: actions/setup-python@v5
	with:
	python-version: 3.x
	- name: test
	shell: bash
	run: \|
	# setup-python puts `python` into the `PATH`, not `python3`, yet
	# `git-filter-repo` expects `python3` in the `PATH`. Let's add
	# a shim.
	printf '#!/bin/sh\n\nexec python "$@"\n' >python3 &&

	export PATH=$PWD:$PATH &&

	if ! t/run_tests -q -v -x
	then
	mkdir failed &&
	tar czf failed/failed.tar.gz t
	exit 1
	fi
	- name: upload failed tests' directories
	if: failure()
	uses: actions/upload-artifact@v4
	with:
	name: failed-${{ matrix.os }}
	path: failed

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