fix(@angular/build): json and json-summary as vitest coverage reporters

They can be quite handy for analysis tools. See https://github.com/vitest-dev/vitest/blob/93f3200e452874ed4e2d018718bbbde7ebd28590/test/coverage-test/test/configuration-options.test-d.ts#L152 for all the current valid options

Author: cexbrayat

packages/angular/build/src/builders/unit-test/schema.json

@@ -98,7 +98,16 @@
  "required": ["buildTarget", "tsConfig", "runner"],
  "definitions": {
  "coverage-reporters": {
- "enum": ["html", "lcov", "lcovonly", "text", "text-summary", "cobertura"]
+ "enum": [
+ "html",
+ "lcov",
+ "lcovonly",
+ "text",
+ "text-summary",
+ "cobertura",
+ "json",
+ "json-summary"
+ ]
  }
  }
 }