fix: segmented button imports wrong path

Fixes #461.

Author: hperrin

packages/segmented-button/src/Segment.svelte

@@ -35,7 +35,7 @@
 >
 
 <script lang="ts">
-  import { MDCSegmentedButtonSegmentFoundation } from '@material/segmented-button/segment/foundation.js';
+  import { MDCSegmentedButtonSegmentFoundation } from '@material/segmented-button';
   import { onMount, getContext } from 'svelte';
   import { get_current_component } from 'svelte/internal';
   import type { ActionArray } from '@smui/common/internal';

packages/segmented-button/src/SegmentedButton.svelte

@@ -26,7 +26,7 @@
 </div>
 
 <script lang="ts">
-  import { MDCSegmentedButtonFoundation } from '@material/segmented-button/segmented-button/foundation.js';
+  import { MDCSegmentedButtonFoundation } from '@material/segmented-button';
   import { onMount, setContext } from 'svelte';
   import { writable } from 'svelte/store';
   import { get_current_component } from 'svelte/internal';