Align inputs in forms using CSS instead of <label>&nbsp;</label>

[podliashanyk]

Label tags like this <label>&nbsp;</label> are used solely for styling in NAV (which is both semantically ill-suited and a bad practice when it comes to accessibility).
...
So the SonarCloud complaint is technically correct, but factually <label>&nbsp;</label> is not used in form control.

Originally posted by @podliashanyk in #3139 (comment)

Occurrences:

• python/nav/web/templates/alertprofiles/filter_form.html - alertprofiles/filters/new, alertprofiles/filters/edit/<filter_id>
• python/nav/web/templates/custom_crispy_templates/submit_field.html - anything calling SubmitField with has_empty_label=True