Enable codespell to automatically check for spelling mistakes

[aloisklink]

Is your feature request related to a problem? Please describe.

We're occasionally making typos in the edgesec documentation. Having an automated spellchecker would help fix this.

Discussed in #504 (comment)

Describe the solution you'd like

It may be worth enabling something like codespell. It easily integrates with `pre-commit, so it should be pretty easy to run. The only issue is fixing all the false positives.

Describe alternatives you've considered

cspell is pretty popular in the Node.JS eco-system. However, because it requires Node.JS (which is pretty massive), it's not a great fit for our project.

codespell uses Python, which is already something we need, due to our dependency on pre-commit.

Additional context

It may not be worth enabling, as it may cause a bunch of false positives. Another thing that might help is enabling Doxygen warnings, since I'm sure that some of our docs might not be rendering properly.