Bump certifi from 2022.12.7 to 2023.7.22 in /testapp

Bumps [certifi](https://github.com/certifi/python-certifi) from 2022.12.7 to 2023.7.22.
- [Commits](certifi/python-certifi@2022.12.07...2023.07.22)

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

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

Author: dependabot[bot]

testapp/requirements.txt

@@ -1,6 +1,6 @@
 asgiref==3.6.0
 attrs==21.4.0
-certifi==2022.12.7
+certifi==2023.7.22
 charset-normalizer==2.0.12
 jinja2
 idna==3.3