fix(notificaiton/breadcrumb): update styles/remove @extend (#10231)

### Related Ticket(s)

N/A
### Description

with update to `sass` we need to import 

### Changelog

**Changed**

- added styles from react package not coming through


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packages/carbon-web-components/src/components/breadcrumb/breadcrumb.scss

@@ -17,6 +17,12 @@ $css--plex: true !default;
 
 :host(#{$prefix}-breadcrumb-item) {
   @extend .#{$prefix}--breadcrumb-item;
+
+  &::after {
+    margin-left: $spacing-03;
+    color: $text-primary;
+    content: '/';
+  }
 }
 
 :host(#{$prefix}-breadcrumb-overflow-menu) {

packages/carbon-web-components/src/components/notification/inline-notification.scss

@@ -1,5 +1,5 @@
 //
-// Copyright IBM Corp. 2019, 2022
+// Copyright IBM Corp. 2019, 2023
 //
 // This source code is licensed under the Apache-2.0 license found in the
 // LICENSE file in the root directory of this source tree.
@@ -30,38 +30,52 @@ $css--plex: true !default;
   display: none;
 }
 
+:host(#{$prefix}-inline-notification[low-contrast]) {
+  &[low-contrast] {
+    @extend .#{$prefix}--inline-notification--low-contrast;
+  }
+}
+
 :host(#{$prefix}-inline-notification[kind='success']) {
   @extend .#{$prefix}--inline-notification--success;
 
   &[low-contrast] {
-    @extend .#{$prefix}--inline-notification--low-contrast,
-      .#{$prefix}--inline-notification--success;
+    @include notification--experimental(
+      $support-success,
+      get-token-value($notification-colors, 'notification-background-success')
+    );
   }
 }
 
 :host(#{$prefix}-inline-notification[kind='info']) {
   @extend .#{$prefix}--inline-notification--info;
 
   &[low-contrast] {
-    @extend .#{$prefix}--inline-notification--low-contrast,
-      .#{$prefix}--inline-notification--info;
+    @include notification--experimental(
+      $support-info,
+      get-token-value($notification-colors, 'notification-background-info')
+    );
   }
 }
 
 :host(#{$prefix}-inline-notification[kind='warning']) {
   @extend .#{$prefix}--inline-notification--warning;
 
   &[low-contrast] {
-    @extend .#{$prefix}--inline-notification--low-contrast,
-      .#{$prefix}--inline-notification--warning;
+    @include notification--experimental(
+      $support-warning,
+      get-token-value($notification-colors, 'notification-background-warning')
+    );
   }
 }
 
 :host(#{$prefix}-inline-notification[kind='error']) {
   @extend .#{$prefix}--inline-notification--error;
 
   &[low-contrast] {
-    @extend .#{$prefix}--inline-notification--low-contrast,
-      .#{$prefix}--inline-notification--error;
+    @include notification--experimental(
+      $support-error,
+      get-token-value($notification-colors, 'notification-background-error')
+    );
   }
 }

packages/carbon-web-components/src/components/notification/toast-notification.scss

@@ -1,5 +1,5 @@
 //
-// Copyright IBM Corp. 2019, 2022
+// Copyright IBM Corp. 2019, 2023
 //
 // This source code is licensed under the Apache-2.0 license found in the
 // LICENSE file in the root directory of this source tree.
@@ -26,38 +26,52 @@ $css--plex: true !default;
   display: none;
 }
 
+:host(#{$prefix}-toast-notification[low-contrast]) {
+  &[low-contrast] {
+    @extend .#{$prefix}--toast-notification--low-contrast;
+  }
+}
+
 :host(#{$prefix}-toast-notification[kind='success']) {
   @extend .#{$prefix}--toast-notification--success;
 
   &[low-contrast] {
-    @extend .#{$prefix}--toast-notification--low-contrast,
-      .#{$prefix}--toast-notification--success;
+    @include notification--experimental(
+      $support-success,
+      get-token-value($notification-colors, 'notification-background-success')
+    );
   }
 }
 
 :host(#{$prefix}-toast-notification[kind='info']) {
   @extend .#{$prefix}--toast-notification--info;
 
   &[low-contrast] {
-    @extend .#{$prefix}--toast-notification--low-contrast,
-      .#{$prefix}--toast-notification--info;
+    @include notification--experimental(
+      $support-info,
+      get-token-value($notification-colors, 'notification-background-info')
+    );
   }
 }
 
 :host(#{$prefix}-toast-notification[kind='warning']) {
   @extend .#{$prefix}--toast-notification--warning;
 
   &[low-contrast] {
-    @extend .#{$prefix}--toast-notification--low-contrast,
-      .#{$prefix}--toast-notification--warning;
+    @include notification--experimental(
+      $support-warning,
+      get-token-value($notification-colors, 'notification-background-warning')
+    );
   }
 }
 
 :host(#{$prefix}-toast-notification[kind='error']) {
   @extend .#{$prefix}--toast-notification--error;
 
   &[low-contrast] {
-    @extend .#{$prefix}--toast-notification--low-contrast,
-      .#{$prefix}--toast-notification--error;
+    @include notification--experimental(
+      $support-error,
+      get-token-value($notification-colors, 'notification-background-error')
+    );
   }
 }