Update master branch references to main where suitable #369

	name: Test
	on: [pull_request]

	jobs:
	test-registry:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	image_name: ['repo2docker-test', '']
	tag: ['test-tag', '']
	no_push: [true, '']
	latest_off: [true, '']
	services:
	local-registry:
	image: registry:2
	ports:
	- 5000:5000
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	- name: test action
	uses: ./
	with:
	IMAGE_NAME: ${{ matrix.image_name }}
	ADDITIONAL_TAG: ${{ matrix.tag }}
	NO_PUSH: ${{ matrix.push }}
	LATEST_TAG_OFF: ${{ matrix.latest_off }}
	DOCKER_REGISTRY: "localhost:5000"
	DOCKER_USERNAME: 'foo'
	DOCKER_PASSWORD: 'foo'

	mybinder:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout PR
	uses: actions/checkout@v2

	- name: mybinder
	uses: ./
	with:
	NO_PUSH: true
	MYBINDERORG_TAG: ${{ github.sha }}

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