Bump twisted from 19.2.0 to 19.7.0

Bumps [twisted](https://github.com/twisted/twisted) from 19.2.0 to 19.7.0.
- [Release notes](https://github.com/twisted/twisted/releases)
- [Changelog](https://github.com/twisted/twisted/blob/trunk/NEWS.rst)
- [Commits](twisted/twisted@twisted-19.2.0...twisted-19.7.0)

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

Author: dependabot[bot]

requirements.txt

@@ -43,7 +43,7 @@ sgmllib3k==1.0.0
 six==1.12.0
 soupsieve==1.9
 tldextract==2.2.1
-Twisted==19.2.0
+Twisted==19.7.0
 urllib3==1.24.2
 w3lib==1.20.0
 win-inet-pton==1.0.1