v1.8.12

• #207: ci: Update GitHub Actions
• #208: Provide better support for toolchains for JVM projects
• #211: Avoid warning about --add-opens from compileTestJava task
• #212: Fix for Kotlin 1.7 breaking changes
• #213: Make it easier to test locally

Many thanks to @KengoTODA and @big-andy-coates for their contributions!