Bump certifi from 2023.5.7 to 2023.7.22 in /model-engine (#218)

Bumps [certifi](https://github.com/certifi/python-certifi) from 2023.5.7 to 2023.7.22.
- [Commits](certifi/python-certifi@2023.05.07...2023.07.22)

---
updated-dependencies:
- dependency-name: certifi
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Phil Chen <[email protected]>

Author: dependabot[bot]

model-engine/requirements.txt

@@ -60,7 +60,7 @@ cachetools==5.3.1
     # via google-auth
 celery[redis,sqs,tblib]==5.3.1
     # via -r requirements.in
-certifi==2023.5.7
+certifi==2023.7.22
     # via
     #   datadog-api-client
     #   kubernetes