fix(checkbox): adjust required asterisk spacing to bring it directly to the label

[michaelmkraus]

Proposed changes

• fix(checkbox): adjust required asterisk spacing to bring it directly to the label
  Use negative margin on the ::after to offset the flex gap, bringing the asterisk directly next to the label without affecting
  the gap between the checkbox icon and the label.
• also fixes this issue for radio and switch

closes #3038

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (fix on existing components or architectural decisions)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

[github-actions]

🔭🐙🐈 Test this branch here: https://db-ux-design-system.github.io/core-web/review/fix-checkbox-required-gap-to-asteriks

[nmerget]

@michaelmkraus this would not work for textarea, input and select

Maybe you can change the label stylings for switch and checkbox, by removing the gap: var(--db-spacing-fixed-xs); and add label > input {margin-inline-end: db-spacing-fixed-xs}