Spelling errors are unclear in pull request CI results and spell checker is unmaintained

[wallrj]

When the spell-checker is run from CI for a PR and fails, the results are not syntax highlighted so it's difficult to know which word caused the failure. For example:

https://prow.build-infra.jetstack.net/view/gs/jetstack-logs/pr-logs/pull/cert-manager_website/797/pull-cert-manager-website-verify/1483400121444995072

We use https://github.com/lukeapage/node-markdown-spellcheck which seems to be unmaintained. Its dependencies are out-of-data and causing false-alarms from Dependabot

https://github.com/cert-manager/website/security/dependabot/package-lock.json/marked/open

Perhaps we should use a different spell checker. For example:

• https://github.com/kubernetes/website/pull/26228
• https://github.com/cncf/glossary/pull/111
• https://megalinter.github.io/latest/descriptors/spell/

/bug

[jsoref]

Well, you could use https://github.com/marketplace/actions/check-spelling 😺