Bump simplejson from 3.16.0 to 3.17.0

Bumps [simplejson](https://github.com/simplejson/simplejson) from 3.16.0 to 3.17.0.
- [Release notes](https://github.com/simplejson/simplejson/releases)
- [Changelog](https://github.com/simplejson/simplejson/blob/master/CHANGES.txt)
- [Commits](simplejson/simplejson@v3.16.0...v3.17.0)

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

requirements.txt

@@ -27,7 +27,7 @@ python-dateutil==2.8.1
 repoze.lru==0.7
 repoze.sendmail==4.4.1
 requests==2.22.0
-simplejson==3.16.0
+simplejson==3.17.0
 transaction==2.4.0
 translationstring==1.3
 ujson==1.35