fix(files): improve aria attributes on search toggle button

add aria-pressed to convey toggle state, use static aria-label,
and hide decorative SVG icon from screen readers.

Author: lidel

src/files/FilesPage.js

@@ -377,10 +377,11 @@ const FilesPage = ({
             className="pointer selected-item ml2"
             onClick={toggleSearch}
             title={showSearch ? t('hideSearch') : t('showSearch')}
-            aria-label={showSearch ? t('hideSearch') : t('showSearch')}
+            aria-label={t('showSearch')}
+            aria-pressed={showSearch}
             style={{ height: '24px' }}
           >
-            <GlyphSearch width="24" height="24" fill="currentColor" />
+            <GlyphSearch width="24" height="24" fill="currentColor" aria-hidden="true" />
           </button>
         </div>
       </Header>