Add labels to two buttons that were missing them (#20419) (#20524)

Backport #20419

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

templates/base/head_navbar.tmpl

@@ -114,7 +114,7 @@
 				</div>
 			</div>
 
-			<a href="{{AppSubUrl}}/notifications" class="item tooltip not-mobile" data-content='{{.i18n.Tr "notifications"}}'>
+			<a href="{{AppSubUrl}}/notifications" class="item tooltip not-mobile" data-content="{{.i18n.Tr "notifications"}}" aria-label="{{.i18n.Tr "notifications"}}">
 				<span class="text">
 					<span class="fitted">{{svg "octicon-bell"}}</span>
 					<span class="ui red label {{if not $notificationUnreadCount}}hidden{{end}} notification_count">

templates/repo/clone_buttons.tmpl

@@ -19,6 +19,6 @@
 		document.getElementById('repo-clone-url').value = btn ? btn.getAttribute('data-link') : '';
 	})();
 </script>
-<button class="ui basic icon button tooltip" id="clipboard-btn" data-content="{{.i18n.Tr "copy_url"}}" data-clipboard-target="#repo-clone-url">
+<button class="ui basic icon button tooltip" id="clipboard-btn" data-content="{{.i18n.Tr "copy_url"}}" data-clipboard-target="#repo-clone-url" aria-label="{{.i18n.Tr "copy_url"}}">
 	{{svg "octicon-paste"}}
 </button>