build(deps): bump undici and @angular-devkit/build-angular in /demo

Bumps [undici](https://github.com/nodejs/undici) to 6.7.1 and updates ancestor dependency [@angular-devkit/build-angular](https://github.com/angular/angular-cli). These dependencies need to be updated together. Updates `undici` from 6.2.1 to 6.7.1 - [Release notes](https://github.com/nodejs/undici/releases) - [Commits](nodejs/undici@v6.2.1...v6.7.1) Updates `@angular-devkit/build-angular` from 17.1.2 to 17.3.0 - [Release notes](https://github.com/angular/angular-cli/releases) - [Changelog](https://github.com/angular/angular-cli/blob/main/CHANGELOG.md) - [Commits](angular/angular-cli@17.1.2...17.3.0) --- updated-dependencies: - dependency-name: undici dependency-type: indirect - dependency-name: "@angular-devkit/build-angular" dependency-type: direct:development ... Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]