Bump venusian from 1.1.0 to 1.2.0

Bumps [venusian](https://github.com/Pylons/venusian) from 1.1.0 to 1.2.0.
- [Release notes](https://github.com/Pylons/venusian/releases)
- [Changelog](https://github.com/Pylons/venusian/blob/master/CHANGES.rst)
- [Commits](Pylons/venusian@1.1.0...1.2.0)

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

requirements.txt

@@ -32,7 +32,7 @@ transaction==2.4.0
 translationstring==1.3
 ujson==1.35
 urllib3==1.24.1
-venusian==1.1.0
+venusian==1.2.0
 waitress==1.1.0
 WebOb==1.7.4
 zope.deprecation==4.4.0