remove sudo: in .travis.yml

https://blog.travis-ci.com/2018-11-19-required-linux-infrastructure-migration

Committed via https://github.com/asottile/all-repos

.travis.yml

diff --git a/.travis.yml b/.travis.yml
index 2868833..477b5c4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,4 @@
 language: python
-sudo: false
 matrix:
     include:  # These should match the tox env list
     -   env: TOXENV=py27
@@ -7,7 +6,6 @@
         python: 3.6
     -   env: TOXENV=py37
         python: 3.7
-        sudo: required
         dist: xenial
     -   env: TOXENV=pypy
         python: pypy-5.7.1