1.8.9-r0

• Flarum 1.8.9 by @crazy-max in #122
• Handle install/removal of multiple extensions by @DoyoDia @crazy-max in #121
• Alpine Linux 3.21 by @crazy-max in #123
• DB_SKIP_SSL env var by @crazy-max in #123

Full Changelog: 1.8.8-r0...1.8.9-r0