Tweak UI for new SRT

[jernestmyers]

Addresses the following points from this issue:

1. Mockup updated after UX meeting Jan 18 2023 https://docs.google.com/presentation/d/1m43IHO6BnkXHpusYR2cnJgWdgazm8jCy1euqBiNyKRA/edit#slide=id.p
2. Add a checkbox as in the tabular reporter to select one transcript per gene to all report forms where this is now supported. See
   SRT reporter: add flag to download only one transcript per gene (the longest in the result) ApiCommonWebsite#117

Below is a screenshot of the UI changes modeled off of this mockup.

Note that there's a comment in the code that wonders if the flattening of the defline options, which requires adding gene_id to the deflineFields array, would cause trouble with the backend. It does not appear to break anything. I tested my branch with a local dev server pointed at @ryanrdoherty's dev site and the same reports succeed and fail when using this branch versus main.

[dmfalke]

This looks great!

[aurreco-uga]

@jernestmyers could you remove the 1 transcript option in record types other than genes?