Remove sith test from travis. Never looked it it. Just run it locally

.travis.yml

@@ -16,15 +16,12 @@ env:
 matrix:
   allow_failures:
     - python: pypy
-    - env: TOXENV=sith
     - python: 3.8-dev
   include:
     - python: 3.6
       env:
         - TOXENV=cov
         - JEDI_TEST_ENVIRONMENT=36
-    - python: 3.6
-      env: TOXENV=sith
     # For now ignore pypy, there are so many issues that we don't really need
     # to run it.
     #- python: pypy