Bump pillow from 4.3.0 to 9.0.0

Bumps [pillow](https://github.com/python-pillow/Pillow) from 4.3.0 to 9.0.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/main/CHANGES.rst)
- [Commits](python-pillow/Pillow@4.3.0...9.0.0)

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

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

Author: dependabot[bot]

requirements.txt

@@ -18,7 +18,7 @@ html5lib==1.0b10
 httplib2==0.10.3
 idna==2.6
 olefile==0.44
-Pillow==4.3.0
+Pillow==9.0.0
 PyPDF2==1.26.0
 pypng==0.0.18
 PyQRCode==1.2.1