plugin-json-archetype generates a sample that might not be the right way to do code-completion

[vazexqi]

Repro steps:

1. docker run -it --rm -v /var/run/docker.sock:/var/run/docker.sock -v /Users/nchen/che/data:/data -v /Users/nchen/Development/che-sample:/archetype -v /Users/nchen/.m2/repository:/m2 eclipse/che-cli:5.15.0 archetype generate --group=com.vazexqi.sample
2. Fix the issue with the generated Constants.jave (see plugin-json-archetype generates project with compile errors (Constants.java) #55)
3. Build with MAVEN_OPTS="-Xmx3000m" mvn clean install
4. Run with docker run -it --rm -v /var/run/docker.sock:/var/run/docker.sock -v /Users/nchen/che/data:/data -v /Users/nchen/Development/che-sample:/archetype eclipse/che-cli:5.15.0 archetype run

The JSON auto-completion sample basically destroys the text editor. The contents is messed up. The lines are messed up. Try to undo (Cmd+Z) and the line numbers are gone. See the attached gif.