build(deps): bump jekyll from 3.8.5 to 3.9.1

[dependabot-preview]

Bumps jekyll from 3.8.5 to 3.9.1.

Release notes

Sourced from jekyll's releases.

v3.9.1

Bug Fixes

• Backport #8618 for v3.9.x: Update include tag to be more permissive (#8629)

v3.9.0

Minor Enhancements

• Allow use of kramdown v2 (#8322)
• Add default language for kramdown syntax highlighting (#8325)

v3.8.7

Fixes

• Prevent console warnings with Ruby 2.7 (#7948)

v3.8.6

Bug Fixes

• Update log output for an invalid theme directory (#7734)
• Memoize SiteDrop#documents to reduce allocations (#7722)
• Excerpt handling of custom and intermediate tags (#7467)
• Escape valid special chars in a site's path name (#7573)
• Revert memoizing Site#docs_to_write and refactor #documents (#7689)
• Fix broken include_relative usage in excerpt (#7690)
• Install platform-specific gems as required (3c06609406)

Security Fixes

• Theme gems: ensure directories aren't symlinks (#7424)

Changelog

Sourced from jekyll's changelog.

3.9.1 / 2021-04-08

Bug Fixes

• Backport #8618 for v3.9.x: Update include tag to be more permissive (#8629)

3.9.0 / 2020-08-05

Minor Enhancements

• Allow use of kramdown v2 (#8322)
• Add default language for kramdown syntax highlighting (#8325)

3.8.7 / 2020-05-08

Bug Fixes

• Prevent console warnings with Ruby 2.7 (#8125)

4.0.0 / 2019-08-19

Major Enhancements

• Drop ruby 2.3 (#7454)
• Drop support for Ruby 2.1 and 2.2 (#6560)
• Drop support for older versions of Rouge (#6978)
• Drop support for pygments as syntax-highlighter (#7118)
• Drop support for Redcarpet (#6987)
• Drop support for rdiscount (#6988)
• Drop support for jekyll-watch-1.4.0 and older (#7287)
• Incorporate relative_url filter in link tag (#6727)
• Upgrade kramdown dependency to v2.x (#7492)
• Upgrade jekyll-sass-converter to v2.x - Sassc + sourcemaps (#7778)
• Upgrade i18n to v1.x (#6931)
• Add Jekyll::Cache class to handle caching on disk (#7169)
• Cache converted markdown (#7159)
• Cache: Do not dump undumpable objects (#7190)
• Cache matched defaults sets for given parameters (#6888)
• Ignore cache directory (#7184)
• Add Site#in_cache_dir helper method (#7160)
• Remove 'cache_dir' during jekyll clean (#7158)
• Cache parsed Liquid templates in memory (#7136)
• Only read layouts from source_dir or theme_dir (#6788)
• Allow custom sorting of collection documents (#7427)
• Always exclude certain paths from being processed (#7188)
• Remove Jekyll::Utils#strip_heredoc in favor of a Ruby > 2.3 built in (#7584)
• Incorporate relative_url within post_url tag (#7589)
• Remove patch to modify config for kramdown (#7699)

Minor Enhancements

... (truncated)

Commits

• c50821b Release 💎 3.9.1
• 970f3a1 Merge pull request #8631 from jekyll/3.9-stable-3-9-1-release-post
• 7f11845 Release post for v3.9.1
• 2b31497 Remove calls to Regexp#freeze as it's an immutable object.
• 9bdb9c9 Merge pull request #8629 from jekyll/3.9-stable-backport-8618
• 672da32 Backport update-include-tag-to-be-more-permissive from #8618 to 3.9-stable
• 8fe3a5d Release 💎 3.9.0
• 331361a Update jekyll 3.9.0 release post
• 8681d67 Update history.markdown
• 917c7b1 [3.x] Add default language for kramdown syntax highlighting (#8325)
• Additional commits viewable in compare view

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