Bump flask in /test/sagemaker_tests/pytorch/inference

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>

Author: dependabot[bot]

test/sagemaker_tests/pytorch/inference/requirements.txt

@@ -2,7 +2,7 @@ boto3
 coverage==4.5.3
 docker-compose
 flake8==3.7.7
-Flask==1.1.1
+Flask==2.2.5
 mock==2.0.0
 pytest==4.4.0
 pytest-cov==2.7.1