Bump flask-restx from 0.4.0 to 0.5.1 in /report-api

Bumps [flask-restx](https://github.com/python-restx/flask-restx) from 0.4.0 to 0.5.1.
- [Release notes](https://github.com/python-restx/flask-restx/releases)
- [Changelog](https://github.com/python-restx/flask-restx/blob/master/CHANGELOG.rst)
- [Commits](python-restx/flask-restx@0.4.0...0.5.1)

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

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

report-api/requirements.txt

@@ -20,7 +20,7 @@ cssselect2==0.4.1
 defusedxml==0.7.1
 ecdsa==0.14.1
 flask-jwt-oidc==0.3.0
-flask-restx==0.4.0
+flask-restx==0.5.1
 gunicorn==20.1.0
 html5lib==1.1
 idna==2.10