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?

從 ng test 命令及其在 angular.json 中的測試選項開始，然後將現有的 reporters 選項與所要求的 coverageReporters 行為進行比較。檢查 --code-coverage 和 Karma 設定目前如何處理 coverage；當 ng test --code-coverage --coverage-reporters lcov 選取要求的 reporter，且 angular.json 中的對應選項可以運作時，即表示完成。

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