Some bug fixes and bump the minimum supported Rust version to 1.61

Changes

• Support CDATA in RSS2.0 categories and DublinCore authors (thanks @davidcornu !)
• Upgrade regex and url dependencies (minor versions)
• Bump MSVR to 1.61 following freedesktop-sdk
• Upgrade quick-xml to 0.25 (thanks @davidcornu )
• Merge fixed fuzz test following the url crate update (thanks for the original fuzz work @rillian )
• Drop empty enclosures in the Matrix RSS 2.0 feed (thanks for a great bug report as always @jangernert )