Update Windows MDM end user experience language (#47635)

**Related issue:** Resolves #43379

# Checklist for submitter

- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.


## Testing

- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Style**
* Updated Windows MDM enrollment option labels from “Automatic/Manual”
to “Fleet agent-driven/End user-driven” and refreshed the related
on-page description/help text.
* Adjusted radio help-text spacing and added styling for label
formatting on the Windows MDM settings page.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

frontend/components/forms/fields/Radio/_styles.scss

@@ -73,7 +73,6 @@
   &__help-text {
     @include help-text;
     margin-top: $pad-xxsmall;
-    margin-left: calc(20px + #{$pad-small});
   }
 
   &__disabled {