Bump flatted in /user-propagation-via-xsuaa/angular-example-app

Bumps [flatted](https://github.com/WebReflection/flatted) from 3.2.5 to 3.4.2.
- [Commits](WebReflection/flatted@v3.2.5...v3.4.2)

---
updated-dependencies:
- dependency-name: flatted
  dependency-version: 3.4.2
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]