build(deps): bump follow-redirects from 1.15.3 to 1.15.4 in /docs

Bumps [follow-redirects](https://github.com/follow-redirects/follow-redirects) from 1.15.3 to 1.15.4.
- [Release notes](https://github.com/follow-redirects/follow-redirects/releases)
- [Commits](follow-redirects/follow-redirects@v1.15.3...v1.15.4)

---
updated-dependencies:
- dependency-name: follow-redirects
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>