rake-runner in Kotlin DSL enabling bundler by default

I'm experimenting with use of the Kotlin DSL and have the following problem:

When adding a rake-runner step, bundler exec is added by default. Even if I uncheck the boxes and save, the DSL script is not changed - changing the option in the UI deactivates bundler, but if I recreate the job from the VCS the checkbox is activated again (as it is the default option).

Looking through the code for rake-runner, I see it uses a constant for this setting and it is always enabled. Is there a way of disabling it in the DSL?

I'm on TeamCity 2019.2