Use a single Scarpe::App instance as self nearly everywhere #772

	---
	name: CI
	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	jobs:
	tests:
	name: Tests
	runs-on: macos-latest
	timeout-minutes: 10
	steps:
	- name: Install dependencies
	run: brew install pkg-config portaudio
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Setup Ruby and install gems
	uses: ruby/setup-ruby@v1
	with:
	bundler-cache: true
	- name: Run tests
	run: CI_RUN='true' bundle exec rake test
	- name: upload test-fail logs
	if: '!cancelled()'
	uses: actions/upload-artifact@v3
	with:
	name: test failure logs
	path: logger/test_failure*.out.log
	linter:
	name: Linter
	runs-on: macos-latest
	timeout-minutes: 10
	steps:
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Setup Ruby and install gems
	uses: ruby/setup-ruby@v1
	with:
	bundler-cache: true
	- name: Run linter
	run: bundle exec rubocop

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