Bump pillow from 6.2.0 to 7.1.0

Bumps [pillow](https://github.com/python-pillow/Pillow) from 6.2.0 to 7.1.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/master/CHANGES.rst)
- [Commits](python-pillow/Pillow@6.2.0...7.1.0)

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

requirements.txt

@@ -14,7 +14,7 @@ lxml==4.6.2
 mccabe==0.6.1
 newspaper3k==0.2.8
 nltk==3.4.5
-Pillow==6.2.0
+Pillow==7.1.0
 pylint==2.4.1
 pylint-django==2.0.11
 pylint-plugin-utils==0.5