Update pelican to 4.2.0

[pyup-bot]

This PR updates pelican from 4.0.1 to 4.2.0.

Changelog

4.2.0

==================

* Support inline SVGs; don't treat titles in SVGs as HTML titles
* Add category to feeds (in addition to tags)
* Improve content metadata field docs
* Add docs for including other Markdown/reST files in content

4.1.3

==================

* Fix quick-start docs regarding `pelican --listen`
* Set default listen address to 127.0.0.1
* Add extra/optional Markdown dependency to setup.py
* Use correct SSH port syntax for rsync in tasks.py
* Place all deprecated settings handling together
* Add related project URLs for display on PyPI
* Skip some tests on Windows that can't pass due to filesystem differences

4.1.2

==================

Fix pelican.settings.load_source to avoid caching issues - PR 2621

4.1.1

==================

* Add AutoPub to auto-publish releases on PR merge
* Add CSS classes for reStructuredText figures
* Pass `argv` to Pelican `main` entrypoint
* Set default content status to a blank string rather than `None`

4.1.0

==================

* Live browser reload upon changed files (provided via Invoke task)
* Add ``pyproject.toml``, managed by Poetry
* Support for invoking ``python -m pelican``
* Add relative source path attribute to content
* Allow directories in ``EXTRA_PATH_METADATA``
* Add ``all_articles`` variable to period pages (for recent posts functionality)
* Improve debug mode output
* Remove blank or duplicate summaries from Atom feed
* Fix bugs in pagination, pelican-import, pelican-quickstart, and feed importer

Links

• PyPI: https://pypi.org/project/pelican
• Changelog: https://pyup.io/changelogs/pelican/
• Homepage: https://getpelican.com/