Bump pillow from 7.1.1 to 8.3.2

Bumps [pillow](https://github.com/python-pillow/Pillow) from 7.1.1 to 8.3.2.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/master/CHANGES.rst)
- [Commits](python-pillow/Pillow@7.1.1...8.3.2)

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

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

requirements.txt

@@ -154,7 +154,7 @@ oauthlib==3.1.0
     # via
     #   django-oauth-toolkit
     #   requests-oauthlib
-pillow==7.1.1
+pillow==8.3.2
     # via -r requirements.in
 psutil==5.7.0
     # via django-gulp