Update plugin for Java 21+ compatibility

[xzel23]

The plugin does not work with current stable Java. I have forked the plugin to be able to build my projects again and will provide a PR. Either my PR (updates ASM, other dependencies, and Gradle wrapper) or PR #152 (updates only the ASM version) should be merged and a new version be released.

[xzel23]

Until a version containing a fix is released, you can use this workaround (change to Groovy syntax if you don't use the Kotlin DSL):

• check out the fork containing this PR

• build the plugin

  ./gradlew build
  

• publish to your local repository

  ./gradlew publishToMavenLocal publishPluginMavenPublicationToMavenLocal publishJLinkPluginMarkerMavenPublicationToMavenLocal
  

• add this to your own project's settings.gradle.kts

  pluginManagement {
      repositories {
          mavenLocal()
          gradlePluginPortal()
      }
  }