Bump pillow from 5.4.1 to 10.3.0 in /doc/sphinx

Bumps [pillow](https://github.com/python-pillow/Pillow) from 5.4.1 to 10.3.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/main/CHANGES.rst)
- [Commits](python-pillow/Pillow@5.4.1...10.3.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

doc/sphinx/requirements.txt

@@ -1,6 +1,6 @@
 sphinx==6.2.1
 sphinx-rtd-theme==1.2.2
-pillow==5.4.1
+pillow==10.3.0
 mock==1.0.1
 commonmark==0.9.1
 recommonmark==0.5.0