Bump certifi from 2022.12.7 to 2023.7.22 in /doc

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>

doc/requirements.txt

@@ -1,7 +1,7 @@
 alabaster==0.7.13
 Babel==2.12.1
 backcall==0.2.0
-certifi==2022.12.7
+certifi==2023.7.22
 chardet==4.0.0
 cycler==0.10.0
 Cython==0.29.33