Run spell checker in a pre-commit hook

[irbekrm]

We often find spelling errors only after having made a PR and have to go back and fix them.

It is possible to run ./scripts/_verify locally before creating the PR, but this seems to be easier forget than i.e running the tests before a code PR as it does not fit into the workflow so well.

As @hawksight suggested we could run the verify script in an optional pre-commit hook https://github.com/cert-manager/website/pull/1049#issuecomment-1209061279