Release summary

See, https://github.com/google/docsy/blob/main/CHANGELOG.md#040

Commit details

• Upgrade Hugo to 0.101.0 by @chalin in #1067
• Breadcrumbs: restore Aria attribute and link by @chalin in #1068
• Set NPM package version to 0.4.0-dev by @chalin in #1069
• Foldable-nav fix by @chalin in #1070
• i18n: es - use var Title in community_how_to by @Marzal in #1060
• Drop Bootstrap and Font Awesome git submodules by @chalin in #889
• Remove obsolete git-submodule scripts from UG package.json by @chalin in #1073
• Docsy 0.4.0 migration instructions and doc updates by @chalin in #1074
• Update fr.toml: post_view_this by @arnaudlevy in #1003
• Update fr.toml: ui_search by @arnaudlevy in #929
• Release 0.4.0 preparation by @chalin in #1078

Full Changelog: v0.3.0...v0.4.0