Bump jekyll from 3.4.3 to 3.6.3 in /src

Bumps [jekyll](https://github.com/jekyll/jekyll) from 3.4.3 to 3.6.3.
- [Release notes](https://github.com/jekyll/jekyll/releases)
- [Changelog](https://github.com/jekyll/jekyll/blob/master/History.markdown)
- [Commits](https://github.com/jekyll/jekyll/compare/v3.4.3...v3.6.3)

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