Add a coverage reporters option to ng test and angular json test options

### Command

test

### Description

It would be nice to be able to specify coverageReporters similar to reporters for ng test

### Describe the solution you'd like

ng test --code-coverage --coverage-reporters lcov

### Describe alternatives you've considered

I could just add a karma conf and configure the coverage reports there, but I can configure excludes for code coverage, why not the reporter?

从 ng test 命令及其在 angular.json 中的测试选项开始，然后将现有的 reporters 选项与所请求的 coverageReporters 行为进行比较。检查 --code-coverage 和 Karma 配置当前如何处理覆盖率；当 ng test --code-coverage --coverage-reporters lcov 选择所请求的 reporter，并且 angular.json 中的等效选项能够正常工作时，即表示完成。

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