CI: add docker cache support #229

	name: tests

	on: [push, pull_request]
	env:
	RUN: docker run -v $GITHUB_WORKSPACE:/project/rednose -w /project/rednose -e PYTHONWARNINGS="error,default::DeprecationWarning" --shm-size 1G --rm rednose /bin/bash -c
	BUILD: docker buildx build --pull --load --cache-to type=inline --cache-from type=registry,ref=ghcr.io/commaai/rednose:latest -t rednose -f Dockerfile .
	PYTHONWARNINGS: error

	jobs:
	unit-tests:
	name: unit tests
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v2
	- name: Build docker image
	run: eval "$BUILD"
	- name: Unit Tests
	run: ${{ env.RUN }} "cd /project/examples; python -m unittest discover"

	static-analysis:
	name: static analysis
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v2
	- name: Build docker image
	run: eval "$BUILD"
	- name: Static analysis
	run: ${{ env.RUN }} "git init && git add -A && pre-commit run --all"

	docker-push:
	name: docker push
	runs-on: ubuntu-20.04
	if: github.ref == 'refs/heads/master' && github.event_name != 'pull_request' && github.repository == 'commaai/rednose'
	steps:
	- uses: actions/checkout@v3
	- name: Build Docker image
	run: eval "$BUILD"
	- name: Push to dockerhub
	run: \|
	docker login ghcr.io -u ${{ github.actor }} -p ${{ secrets.GITHUB_TOKEN }}
	docker tag opendbc ghcr.io/commaai/rednose:latest
	docker push ghcr.io/commaai/rednose:latest

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