fix(@angular/build): validate V8 coverage support for browsers in Vitest

This change introduces a validation check in the Vitest runner to ensure that code coverage is only enabled when using supported Chromium-based browsers. Since the Angular CLI integration currently relies exclusively on the V8 coverage provider, running tests in non-Chromium browsers like Firefox or Safari with coverage enabled would result in incomplete data or missing reports. By adding this check, developers will receive a clear, actionable error message early in the process, preventing confusion and ensuring reliable coverage reports.