Make MAILGUN_URL required field and update README (#12) #28

	---
	name: verify

	on:
	push:
	branches:
	- master
	pull_request:
	types:
	- opened
	- reopened
	- edited
	- synchronize

	jobs:
	hadolint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: hadolint/hadolint-action@v3.1.0
	with:
	dockerfile: Dockerfile

	markdownlint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: articulate/actions-markdownlint@v1

	unittests:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version: '1.22.x'
	- name: Install dependencies
	run: go mod download
	- name: Test with the Go CLI
	run: go test ./...

	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Setup Go
	uses: actions/setup-go@v4
	with:
	go-version: '1.22.x'
	- name: Install dependencies
	run: go mod download
	- name: Build project against .goreleaser.yaml
	uses: goreleaser/goreleaser-action@v6
	with:
	distribution: goreleaser
	version: '~> v2'
	args: build --snapshot
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

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