Flutter 因为邮轮依赖于intl>=0.17.0-nullsafety，需要SDK版本>=2.11.0-180.0.dev<；3.0.0，版本解决失败

今天，当我编译我的项目时，它显示了以下错误：

The current Dart SDK version is 2.10.5.

Because Cruise depends on intl >=0.17.0-nullsafety which requires SDK version >=2.11.0-180.0.dev <3.0.0, version solving failed.
pub get failed (1; Because Cruise depends on intl >=0.17.0-nullsafety which requires SDK version >=2.11.0-180.0.dev <3.0.0, version solving failed.)
Process finished with exit code 1

我不添加

intl>=0.17.0-nullsafety

依赖项。为什么会出现此错误？我应该如何修复它？这是完整的

publispec.yaml

：

name: Cruise
description: A RSS article read Flutter application.

publish_to: 'none'

version: 1.0.0+1

environment:
  sdk: ">=2.7.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  flutter_localizations:
    sdk: flutter
  intl: 0.17.0
  meta: ^1.1.8
  flutter_svg: 0.19.0
  logger: 0.9.4
  scoped_model: ^1.1.0
  shrine_images: ^1.1.2
  flare_dart: 2.3.4
  flare_flutter: ^2.0.2
  vector_math: ^2.0.8
  collection: ^1.14.0
  package_info: ^0.4.0
  fluttertoast: 7.1.6
  #google_fonts: 1.0.0
  flutter_staggered_grid_view: ^0.3.0
  adaptive_breakpoints: ^0.0.2
  cupertino_icons: 1.0.0
  http: ^0.12.0+2
  flutter_icons: ^1.0.0
  timeago: 2.0.26
  animations: 1.1.2
  flutter_hooks: ^0.12.0
  share: ^0.6.4+3
  shimmer: 1.1.1
  crypto: 2.1.5
  url_launcher: 5.5.0
  uni_links: 0.4.0
  flutter_html: 1.2.0
  shared_preferences: ^0.5.8
  state_notifier: ^0.5.0
  flutter_secure_storage: 3.3.3
  flutter_slidable: "^0.5.5"
  hive: ^1.4.1+1
  #fluwx: ^2.4.1
  pull_to_refresh: 1.6.3
  intl_phone_number_input: ^0.5.0
  dio: 3.0.10
  fish_redux: 0.3.4
  hive_flutter: 0.3.1

dev_dependencies:
  flutter_test:
    sdk: flutter
  test:
  path:
  args:
  grinder: ^0.8.0
  pedantic: ^1.9.0
  string_scanner: ^1.0.5

flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true
  generate: true

name:Cruise
描述：RSS文章阅读颤振应用程序。
发布到：“无”
版本：1.0.0+1
环境：
sdk:“>=2.7.0如果您已将颤振更新为最新版本，则在您的
pubspec.yaml
中，您应该有以下行：

environment:
  sdk: ">=2.12.0 <3.0.0"

环境：
sdk:“>=2.12.0 2.12.0不是一个稳定的版本@难道你真的要这么做吗？您上一次进行颤振升级是什么时候⌚ 10:07:21$brew升级dart警告：dart lang/dart/dart 2.10.2已安装（基本版）
@CharStyleιλιαμΑρκεγUhmm，我建议您卸载dart并使用内置dart
environment:
  sdk: ">=2.12.0 <3.0.0"