Add spell-checker to the CI

[szabgab]

Problem

Recently I made a typo #2658

To avoid such mistakes, I'd suggest to add a spell-check to the CI.

I saw this being used axum

On the command line run

cargo install typos-cli

typos --exclude "test_book/" --exclude "*.css" --exclude tests/summary_md_files/the_book-2nd_edition.md --exclude CHANGELOG.md --exclude tests/parse_existing_summary_files.rs --exclude src/front-end/fonts/fontawesome-webfont.svg --exclude src/front-end/searcher/elasticlunr.min.js --exclude ./src/front-end/playground_editor/ace.js --exclude src/front-end/playground_editor/ace.js --exclude src/front-end/js/highlight.js --exclude src/front-end/js/book.js --exclude src/preprocess/links.rs --exclude src/preprocess/links.rs --exclude src/book/book.rs --exclude src/renderer/html_handlebars/hbs_renderer.rs

Right now, using the above exclude list it does not complain. Some of those could be fix, others, like the 3rd-party js files, will have to permanently remain in the exclude list.

Proposed Solution

No response

Notes

No response