fix(dart): update throw Error code snippet (#13067)

* update throw snippet for dart and flutter

* remove file

Author: buenaflor

docs/platforms/dart/common/index.mdx

@@ -78,7 +78,7 @@ Verify that your app is sending events to Sentry by adding the following snippet
 import 'package:sentry/sentry.dart';
 
 try {
-  throw Exception('Sentry Test Error');
+  throw StateError('Sentry Test Error');
 } catch (exception, stackTrace) {
   await Sentry.captureException(
     exception,

docs/platforms/dart/guides/flutter/index.mdx

@@ -144,7 +144,7 @@ Verify that your app is sending events to Sentry by adding the following snippet
 import 'package:sentry/sentry.dart';
 
 try {
-  throw Exception('Sentry Test Exception');
+  throw StateError('Sentry Test Exception');
 } catch (exception, stackTrace) {
   await Sentry.captureException(
     exception,

docs/platforms/dart/guides/flutter/manual-setup.mdx

@@ -110,7 +110,7 @@ Verify that your app is sending events to Sentry by adding the following snippet
 import 'package:sentry/sentry.dart';
 
 try {
-  throw Exception('Sentry Test Exception');
+  throw StateError('Sentry Test Exception');
 } catch (exception, stackTrace) {
   await Sentry.captureException(
     exception,

includes/dart-integrations/logging.mdx

@@ -57,7 +57,7 @@ void main() async {
   log.info('a breadcrumb!');
 
   try {
-    throw Exception();
+    throw StateError();
   } catch (error, stackTrace) {
     log.severe('an error!', error, stackTrace);
   }

platform-includes/capture-error/dart.mdx

@@ -4,7 +4,7 @@ In Dart you can capture any exception object that you caught:
 import 'package:sentry/sentry.dart';
 
 try {
-  throw Exception('Sentry Test Exception');
+  throw StateError('Sentry Test Exception');
 } catch (exception, stackTrace) {
   await Sentry.captureException(
     exception,