v4.0.0

Changes

• Replace Font Awesome by Bootstrap Icons.
• Add support for MyST Markdown. Add new dependency on pelican-myst-reader.
• Remove support for pymdownx and dependency on pymdown-extensions.
• Remove direct dependency on Markdown, pygments.
• Auto-detect location of closure.jar file for webassets.
• Move bump-my-version configuration to pyproject.toml.
• Remove bump2version from dev dependencies, and let the external workflows install it.

🐍 Available on PyPi.