create sample project to demonstrate how Atrium can be used in combination with TestNG

[Robert Stoll]

Platform (all, jvm, js): all
Extension (none, kotlin 1.3): none

Code related feature

• create the project in samples/jvm/testng (see other projects in this folder)
• search for kotest in the repo, and add testng accordingly (e.g. add it to sampels in atrium-samples-test etc.)

Your first contribution?

• Write a comment I'll work on this if you would like to take this issue over.
  This way we get the chance to revise the description in case things have changed in the meantime, we might give you additional hints and we can assign the task to you, so that others do not start as well.
• See Your first code contribution for guidelines.
• Do not hesitate to ask questions here or to contact us via Atrium's slack channel if you need help
  (Invite yourself in case you do not have an account yet).

[Mikołaj Żurawski]

I'll work on this