travis: preemptively switch to VM-based jobs
Rational:
language: python
-sudo: false
cache: pip
dist: trusty
@@ -41,11 +40,9 @@ jobs:
- env: GROUP=1
python: 3.7
dist: xenial
- sudo: required
- env: GROUP=2
python: 3.7
dist: xenial
- sudo: required
- env: GROUP=1
python: 3.5
- env: GROUP=2
@@ -58,11 +55,9 @@ jobs:
- env: GROUP=1
python: 3.8-dev
dist: xenial
- sudo: required
- env: GROUP=2
python: 3.8-dev
dist: xenial
- sudo: required
# It's okay to fail on the in-development CPython version.
fast_finish: true
