Bump tar and @angular/cli in /2023/websocket-angular-example/angular-app

Bumps [tar](https://github.com/isaacs/node-tar) to 7.5.6 and updates ancestor dependency [@angular/cli](https://github.com/angular/angular-cli). These dependencies need to be updated together.


Updates `tar` from 6.1.13 to 7.5.6
- [Release notes](https://github.com/isaacs/node-tar/releases)
- [Changelog](https://github.com/isaacs/node-tar/blob/main/CHANGELOG.md)
- [Commits](isaacs/node-tar@v6.1.13...v7.5.6)

Updates `@angular/cli` from 15.2.6 to 21.1.0
- [Release notes](https://github.com/angular/angular-cli/releases)
- [Changelog](https://github.com/angular/angular-cli/blob/main/CHANGELOG.md)
- [Commits](angular/angular-cli@15.2.6...v21.1.0)

---
updated-dependencies:
- dependency-name: tar
  dependency-version: 7.5.6
  dependency-type: indirect
- dependency-name: "@angular/cli"
  dependency-version: 21.1.0
  dependency-type: direct:development
...

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Author: dependabot[bot]