Bump twisted from 14.0.0 to 20.3.0 in /Holmes/fuzzers

Bumps [twisted](https://github.com/twisted/twisted) from 14.0.0 to 20.3.0.
- [Release notes](https://github.com/twisted/twisted/releases)
- [Changelog](https://github.com/twisted/twisted/blob/trunk/NEWS.rst)
- [Commits](twisted/twisted@twisted-14.0.0...twisted-20.3.0)

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

Holmes/fuzzers/requirements.txt

@@ -1,4 +1,4 @@
-Twisted==14.0.0
+Twisted==20.3.0
 lxml==3.3.5
 psutil==2.1.1
 pyasn1==0.1.7