update pub dependencies

Author: lohanidamodar

templates/flutter/pubspec.yaml.twig

@@ -6,18 +6,17 @@ repository: https://github.com/{{sdk.gitUserName}}/{{sdk.gitRepoName}}
 issue_tracker: https://github.com/appwrite/sdk-generator/issues
 documentation: {{ spec.contactURL }}
 environment:
-  sdk: '>=2.6.0 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 dependencies:
   flutter:
     sdk: flutter
-  cookie_jar: ^1.0.1
-  dio: ^3.0.10
-  dio_cookie_manager: ^1.0.0
-  flutter_web_auth: ^0.2.4
-  meta: ^1.1.8
-  package_info_plus: ^0.6.3
-  path_provider: ^1.6.14
-  universal_html: ^1.2.3
+  cookie_jar: ^3.0.1
+  dio: ^4.0.0
+  dio_cookie_manager: ^2.0.0
+  flutter_web_auth: ^0.3.0
+  package_info_plus: ^1.0.0
+  path_provider: ^2.0.1
+  universal_html: ^2.0.8
 
 dev_dependencies:
   flutter_test: