Bump flask-cors from 4.0.0 to 6.0.0 in /app/frontend

Bumps [flask-cors](https://github.com/corydolphin/flask-cors) from 4.0.0 to 6.0.0.
- [Release notes](https://github.com/corydolphin/flask-cors/releases)
- [Changelog](https://github.com/corydolphin/flask-cors/blob/main/CHANGELOG.md)
- [Commits](corydolphin/flask-cors@4.0.0...6.0.0)

---
updated-dependencies:
- dependency-name: flask-cors
  dependency-version: 6.0.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

app/frontend/requirements.txt

@@ -2,7 +2,7 @@ wheel>=0.40.0
 setuptools>=65.5.1
 Flask==2.2.3; python_version >= "3.7"
 Werkzeug==2.2.3; python_version >= "3.7"
-flask-cors==4.0.0; python_version >= "3.7"
+flask-cors==6.0.0; python_version >= "3.7"
 pika==1.3.0; python_version >= "3.7"
 prometheus-client==0.16.0; python_version >= "3.7"
 requests==2.31.0; python_version >= "3.7"