feat: move web things to inside of the src

Author: arifBurakDemiray

lib/web/countly_flutter_plugin.dart lib/src/web/countly_flutter_plugin.dartlib/web/countly_flutter_plugin.dart renamed to lib/src/web/countly_flutter_plugin.dart

@@ -6,8 +6,8 @@ import 'dart:js_interop';
 import 'dart:js_util';
 
 import 'package:countly_flutter/countly_flutter.dart' as cly;
-import 'package:countly_flutter/web/countly_sdk_web_interop.dart';
-import 'package:countly_flutter/web/json_interop.dart';
+import 'package:countly_flutter/src/web/countly_sdk_web_interop.dart';
+import 'package:countly_flutter/src/web/json_interop.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_web_plugins/flutter_web_plugins.dart';
 

lib/web/countly_sdk_web_interop.dart lib/src/web/countly_sdk_web_interop.dartlib/web/countly_sdk_web_interop.dart renamed to lib/src/web/countly_sdk_web_interop.dart

@@ -34,4 +34,4 @@ flutter:
                 pluginClass: CountlyFlutterPlugin
             web:
                 pluginClass: CountlyFlutterPlugin
-                fileName: web/countly_flutter_plugin.dart
+                fileName: src/web/countly_flutter_plugin.dart