Add support for co-authors

[devinturner]

It appears that when building the authorLine, it does not include any co-authors if applicable.

changelog-action/index.js

Lines 27 to 63 in 18293fb

	function buildSubject ({ writeToFile, subject, author, authorUrl, owner, repo }) {
	const hasPR = rePrEnding.test(subject)
	const prs = []
	let output = subject
	if (writeToFile) {
	const authorLine = author ? ` by [@${author}](${authorUrl})` : ''
	if (hasPR) {
	const prMatch = subject.match(rePrEnding)
	const msgOnly = subject.slice(0, prMatch[0].length * -1)
	output = msgOnly.replace(rePrId, (m, prId) => {
	prs.push(prId)
	return `[#${prId}](${githubServerUrl}/${owner}/${repo}/pull/${prId})`
	})
	output += `*(PR [#${prMatch[1]}](${githubServerUrl}/${owner}/${repo}/pull/${prMatch[1]})${authorLine})*`
	} else {
	output = subject.replace(rePrId, (m, prId) => {
	return `[#${prId}](${githubServerUrl}/${owner}/${repo}/pull/${prId})`
	})
	if (author) {
	output += ` *(commit by [@${author}](${authorUrl}))*`
	}
	}
	} else {
	if (hasPR) {
	output = subject.replace(rePrEnding, (m, prId) => {
	prs.push(prId)
	return author ? `*(PR #${prId} by @${author})*` : `*(PR #${prId})*`
	})
	} else {
	output = author ? `${subject} *(commit by @${author})*` : subject
	}
	}
	return {
	output,
	prs
	}
	}

When generating a changelog, I would like to ensure that all contributing parties are credited.