updated project linter-rules and enforced them

lib/view/pages/more/message/message.dart

@@ -27,7 +27,7 @@ class _MessageState extends State<Message> {
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: const Text("Marianum Message"),
+        title: const Text('Marianum Message'),
       ),
       body: Consumer<MessageProps>(builder: (context, value, child) {
         if(value.primaryLoading()) return const LoadingSpinner();
@@ -43,7 +43,7 @@ class _MessageState extends State<Message> {
                     children: [Icon(Icons.newspaper)],
                   ),
                   title: Text(message.name, overflow: TextOverflow.ellipsis),
-                  subtitle: Text("vom ${message.date}"),
+                  subtitle: Text('vom ${message.date}'),
                   trailing: const Icon(Icons.arrow_right),
                   onTap: () {
                     Navigator.push(context, MaterialPageRoute(builder: (context) => MessageView(basePath: value.getMessagesResponse.base, message: message)));