@alexandravassova thanks alot for the PR! it's greatly appreciated! The icon inside the create test form looks great 😄
The only thing I'm a little skeptic about is when clicking on the custom JS button a new window opens up and it seems a little out of place. I have the following suggestion tell me what you think:

1. I realize this wasn't mentioned in the issue but I think it would be best if we can have the custom JS inside the create test form underneath the body and above the expectations.
   Essentially here:
   

Of course if this button isn't clicked this box would be not visible, and when clicked it will appear. It would be perfect if the button is clicked again when the box is visible it will disappear (but save the contents written)

2. In the scenario tab I suggest to place it here:
   

3. Since we will have it inside the actual test form, we don't need the cancel and submit buttons that the original new window would open up with.

4. Last small thing, the scenario tabs don't have a | divider in between the icons (js editor and duplicate) whereas in the step tabs there is a | divider, can you please add the divider also to the scenarios tab to make it even with the rest of the form?
   

Again thanks a lot! I'm open for any questions/comments you have

ok, i am going to implement your suggestions, they make sense :)

@alexandravassova it looks great and exactly how I pictured it 😄 really nice job!
@manorlh will add his review this hopefully tonight or tomorrow at latest. Thanks a lot for the contribution!

hi, @alexandravassova great work!
I'm going merge it to a feature branch as we need to implement the backend
I think it will count for hacktoberfest but it doesn't just let me know.

We will open an issue today for backend implementation, if you would like to participate LMK
Thanks again for the great PR!