fix: a11y issue on a missing description of that complementary icon

Firefox a11y analysis on developer tools is mentioning the missing description on that complementary icon, so we could easily remove it from the accessibility tree

Author: mfranzke

packages/uikit-workshop/views-twig/partials/patternSection.twig

@@ -19,7 +19,7 @@
     <button class="pl-c-pattern__extra-toggle pl-js-pattern-extra-toggle" id="pl-pattern-extra-toggle-{{partial.patternPartial}}" data-patternpartial="{{ partial.patternPartial }}" title="View Pattern Info">
         <span class="pl-c-pattern__extra-toggle-text pl-c-pattern__extra-toggle-text--expand">Expand</span>
         <span class="pl-c-pattern__extra-toggle-text pl-c-pattern__extra-toggle-text--collapse">Collapse</span>
-        <div class="pl-c-pattern__toggle-icon-wrapper">
+        <div class="pl-c-pattern__toggle-icon-wrapper" aria-hidden="true">
           <svg viewBox="0 0 16 16" width="20" height="20" class="pl-c-pattern__toggle-icon pl-c-pattern__toggle-icon--expand">
             <path fill="currentColor" d="M9 11.5l1.5 1.5 5-5-5-5-1.5 1.5 3.5 3.5z"></path>
             <path fill="currentColor" d="M7 4.5l-1.5-1.5-5 5 5 5 1.5-1.5-3.5-3.5z"></path>

packages/uikit-workshop/views/partials/patternSection.mustache

@@ -18,7 +18,7 @@
 		<button class="pl-c-pattern__extra-toggle pl-js-pattern-extra-toggle" id="pl-pattern-extra-toggle-{{ patternPartial }}" data-patternpartial="{{ patternPartial }}" title="View Pattern Info">
 			<span class="pl-c-pattern__extra-toggle-text pl-c-pattern__extra-toggle-text--expand">Expand</span>
 			<span class="pl-c-pattern__extra-toggle-text pl-c-pattern__extra-toggle-text--collapse">Collapse</span>
-			<div class="pl-c-pattern__toggle-icon-wrapper">
+			<div class="pl-c-pattern__toggle-icon-wrapper" aria-hidden="true">
 				<svg viewBox="0 0 16 16" width="20" height="20" class="pl-c-pattern__toggle-icon pl-c-pattern__toggle-icon--expand">
 					<path fill="currentColor" d="M9 11.5l1.5 1.5 5-5-5-5-1.5 1.5 3.5 3.5z"></path>
 					<path fill="currentColor" d="M7 4.5l-1.5-1.5-5 5 5 5 1.5-1.5-3.5-3.5z"></path>