Update Node package dependencies & GitHub Action versions (#87)

Updated all repository (development) Node packages and GitHub Actions
to the latest versions and adapt to their changes:

- husky [1] - Bumped minimum version from `^6.0.0` to `^7.0.4` [2] where
  `7.0.0` [3] is a major update that allows to remove the
  `.husky/.gitignore` file to simplify the local installation and usage.
- lint-staged [4] - Bumped minimum version from `^11.0.0` to
  `^12.0.4` [6] where `12.0.0` [7] is a major update that allows ESM [8]
  usage.
- prettier [9] - Bumped minimum version from `^2.3.2` to `^2.4.1` [10]
  where `12.0.0` [10].
- remark-cli [11] - Bumped minimum version from `^9.0.0` to `^10.0.0`.

[1]: https://github.com/typicode/husky
[2]: https://github.com/typicode/husky/releases/tag/v7.0.4
[3]: https://github.com/typicode/husky/releases/tag/v7.0.0
[4]: https://github.com/okonet/lint-staged
[5]: https://github.com/okonet/lint-staged/releases/tag/^11.0.0
[6]: https://github.com/okonet/lint-staged/releases/tag/v12.0.2
[7]: https://github.com/okonet/lint-staged/releases/tag/v12.0.0
[8]: https://nodejs.org/api/esm.html
[9]: https://prettier.io
[10]: https://github.com/prettier/prettier/releases/tag/2.4.1
[11]: https://github.com/remarkjs/remark/tree/main/packages/remark-cli

Closes GH-86