Improve node edit page

Problem/Motivation

Use bs_bootstrap or its child theme for node edit page. Does not look good, few layout issues like:

- Missing details.form-wrapper padding,
- Last form group in details.form-wrapper should have 0 bottom margin,
- Checkboxes are overflowing to the left (missing custom-control CSS class on form-group,
- Help icon is too low,
- etc.

We could improve this.