On User Register page Fields have spacing issue.

After Fixing the issue.

Firstly, thanks for raising this issue and your commits and screenshots.

Please see attached further Screenshot's of existing user registration forms here using pre-compiled theme "bootstrap _sass_starter_kit"

Here are a few of my observations:

1. Looking here https://git.drupalcode.org/project/bootstrap_sass_starter_kit/-/blob/1.0... - .user-register-form does not exist in component/form.scss ?
2. Does this change modify every form element (as per your screen shot) or simply add margin-top to the user-register-form class wrapper?
3. form.scss needs to be renamed to _form.scss to be consistent, and to show this file has been reviewed
4. Your description here does not really describe the issue. While I can see that there may be a spacing issue here, is this specific to user registration form, for all forms on the user registration journey, or for all forms? My feeling is the issue described is too specific and in-fact this is a wider issue regarding layout of forms
5. To help with this issue have you utilised the style guide admin module? I have installed and enabled on my site to get a look at how bootstrap styles form elements. Please see attached screenshot. From what I can see it uses a wrapper and the wrapper is spaced in em's. Perhaps we should look to do something similar here?
6. I am a bit confused by the gitlab.yml file. I am not sure how this relates to this issue? Perhaps that change should be a separate issue?