Improve handling of nonexistent user #37

	name: CI
	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	jobs:
	build:
	runs-on: ubuntu-18.04
	steps:
	- uses: actions/checkout@v1
	- name: Build and push Docker image
	run: \|
	echo "building code"
	docker build --target builder .

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