Bump loader-utils and @angular-devkit/build-angular in /testpro

Bumps [loader-utils](https://github.com/webpack/loader-utils) to 1.4.2 and updates ancestor dependency [@angular-devkit/build-angular](https://github.com/angular/angular-cli). These dependencies need to be updated together.


Updates `loader-utils` from 1.2.3 to 1.4.2
- [Release notes](https://github.com/webpack/loader-utils/releases)
- [Changelog](https://github.com/webpack/loader-utils/blob/v1.4.2/CHANGELOG.md)
- [Commits](webpack/loader-utils@v1.2.3...v1.4.2)

Updates `@angular-devkit/build-angular` from 0.801.3 to 15.0.0
- [Release notes](https://github.com/angular/angular-cli/releases)
- [Changelog](https://github.com/angular/angular-cli/blob/main/CHANGELOG.md)
- [Commits](https://github.com/angular/angular-cli/commits/15.0.0)

---
updated-dependencies:
- dependency-name: loader-utils
  dependency-type: indirect
- dependency-name: "@angular-devkit/build-angular"
  dependency-type: direct:development
...

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