build(deps): bump fakeredis from 1.6.1 to 1.7.0 in /backend

Bumps [fakeredis](https://github.com/jamesls/fakeredis) from 1.6.1 to 1.7.0.
- [Release notes](https://github.com/jamesls/fakeredis/releases)
- [Commits](jamesls/fakeredis@1.6.1...1.7.0)

---
updated-dependencies:
- dependency-name: fakeredis
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

backend/requirements-dev.txt

@@ -1,4 +1,4 @@
-fakeredis==1.6.1
+fakeredis==1.7.0
 pre-commit==2.15.0
 pytest==6.2.5
 pytest-responses==0.5.0

backend/requirements.txt

@@ -1,7 +1,7 @@
 -e ../tools #egg=code-coverage-tools
 connexion==2.9.0
 datadog==0.42.0
-fakeredis==1.6.1
+fakeredis==1.7.0
 Flask==1.1.2
 Flask-Cors==3.0.10
 flask-talisman==0.8.1