fix: list margin fix (#5919)

### Related Ticket(s)

#5863

### Description

Carbon list had a bug in which ordered list items required an extra left margin to align correctly. This bug has fixed now and the extra margin is no longer needed.

**Removed**

- Removed extra margin from carbon expressive theme
- Removed `_list.scss` file from theme since it's no longer needed

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<!-- *** "package: services": Services -->
<!-- *** "package: utilities": Utilities -->
<!-- *** "package: styles": Carbon Expressive -->
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packages/styles/scss/themes/expressive/index.scss

@@ -23,7 +23,6 @@
 @import 'components/file-uploader';
 @import 'components/inline-loading';
 @import 'components/inline-notifications';
-@import 'components/list';
 @import 'components/list-box';
 @import 'components/loading';
 @import 'components/modal';
@@ -71,7 +70,6 @@
   @include file-uploader-expressive;
   @include inline-loading-expressive;
   @include inline-notifications-expressive;
-  @include list-expressive;
   @include list-box-expressive;
   @include loading-expressive;
   @include modal-expressive;