Angular - Migrating UI Tests to Vitest

[erdemcaygor]

Resolves #24485

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You can use these commands to run the tests

1. Under the ng-packs directory
   • yarn test:vitest :: runs all tests at once
   • yarn test:vitest:project:: runs tests for core as default and you can give project names as being package labels like this yarn test:vitest:project theme-shared
2. Under the package directories
   • yarn vitest to run all tests
   • yarn vitest --config vitest.config.mts src/lib/tests/initial-utils.spec.ts to run specific tests.