This new version includes a fix for a ReDoS vulnerability in
`semver-regex` that is flagged by some source composition analysis tools
like Snyk:
https://snyk.io/vuln/SNYK-JS-SEMVERREGEX-1047770
It's a major version because it drops support for Node.js 6.x. This
doesn't affect us since we already require Node.js >=10.18.
