Bump flask in /v1/load-generator/backend/services/default

Bumps [flask](https://github.com/pallets/flask) from 1.1.1 to 2.2.5.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](pallets/flask@1.1.1...2.2.5)

---
updated-dependencies:
- dependency-name: flask
  dependency-type: direct:production
...

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

v1/load-generator/backend/services/default/requirements.txt

@@ -1 +1 @@
-Flask==1.1.1
+Flask==2.2.5