boot_serial: Fix `format` warning #49

	on:
	push:
	branches:
	- main
	- v*-branch
	pull_request:

	name: imgtool

	concurrency:
	group: imgtool-${{ github.event.pull_request.number \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	test:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.x", "pypy3.9"]
	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	cache: 'pipenv'
	cache-dependency-path: \|
	scripts/setup.py
	- name: Install dependencies
	run: \|
	pip install --user pipenv
	- name: Run tests
	run: \|
	cd scripts
	pipenv run pip install pytest -e .
	pipenv run pytest --junitxml=../junit/pytest-results-${{ matrix.python-version }}.xml
	- name: Upload test results
	uses: actions/upload-artifact@v3
	if: always()
	with:
	name: pytest-results-${{ matrix.python-version }}
	path: \|
	junit/pytest-results-${{ matrix.python-version }}*.xml
	if-no-files-found: ignore
	environment:
	if: ${{ github.event_name == 'push' }}
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0
	- name: Cache pip
	uses: actions/cache@v1
	with:
	path: ~/.cache/pip
	key: ${{ runner.os }}-pip
	- name: Install packages
	run: \|
	export PATH="$HOME/.local/bin:$PATH"
	./ci/imgtool_install.sh
	- name: Publish
	env:
	TWINE_TOKEN: ${{ secrets.TWINE_TOKEN }}
	run: \|
	export PATH="$HOME/.local/bin:$PATH"
	./ci/imgtool_run.sh

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