Update spec/features/issues/form_spec.rb to new issue look

What does this MR do and why?

Update spec/features/issues/form_spec.rb to new issue look

Now that the new issue look (based on the work items framework) is enabled by default, the feature specs should be updated accordingly

References

How to set up and validate locally

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.