Angular 从角度9升级到角度10时出现问题

我想更新我的angular项目，我使用了以下命令

$ ng update @angular/core@9 @angular/cli@9
$ ng update @angular/core @angular/cli

但在控制台中执行最后一个命令行后，它抛出以下错误

Your global Angular CLI version (10.0.0) is greater than your local
version (9.1.9). The local Angular CLI version is used.

To disable this warning use "ng config -g cli.warnings.versionMismatch false".
The installed local Angular CLI version is older than the latest stable version.
Installing a temporary version to perform the update.
Installing packages for tooling via npm.
Installed packages for tooling via npm.
Using package manager: 'npm'
Collecting installed dependencies...
Found 40 dependencies.
Fetching dependency metadata from registry...
                  Package "@ng-select/ng-option-highlight" has an incompatible peer dependency to "@angular/core" (requires "^8.0.3" (extended), would install "10.0.0").
                  Package "@ng-select/ng-select" has an incompatible peer dependency to "@angular/forms" (requires ">=8.0.0 <9.0.0" 
(extended), would install "10.0.0").
                  Package "@ng-select/ng-option-highlight" has an incompatible peer dependency to "@angular/common" (requires "^8.0.3" (extended), would install "10.0.0").
× Migration failed: Incompatible peer dependencies found.
Peer dependency warnings when installing dependencies means that those dependencies might not work correctly together.
You can use the '--force' option to ignore incompatible peer dependencies and instead address these warnings later.
  See "C:\Users\jfhh\AppData\Local\Temp\ng-riDjkX\angular-errors.log" for further details.

您的全局Angular CLI版本（10.0.0）高于本地版本
版本（9.1.9）。使用本地CLI版本。
要禁用此警告，请使用“ng config-g cli.warnings.versionMismatch false”。
安装的本地CLI版本比最新的稳定版本旧。
安装临时版本以执行更新。
通过npm安装工具包。
通过npm安装工具包。
使用包管理器：“npm”
正在收集已安装的依赖项。。。
找到40个依赖项。
正在从注册表中提取依赖项元数据。。。
包“@ng select/ng option highlight”与“@angular/core”具有不兼容的对等依赖关系（需要“^8.0.3”（扩展），将安装“10.0.0”）。
包“@ng select/ng select”与“@angular/forms”（需要“>=8.0.0不兼容的对等依赖项错误可以通过添加后缀--force来删除
i、 e.使用下面的命令

ng update @angular/core @angular/cli --force

这个错误似乎很明显。你不明白什么？