Bump pillow from 5.2.0 to 5.3.0
Bump pillow from 5.2.0 to 5.3.0

Bumps [pillow](https://github.com/python-pillow/Pillow) from 5.2.0 to 5.3.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/master/CHANGES.rst)
- [Commits](https://github.com/python-pillow/Pillow/compare/5.2.0...5.3.0)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
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