Merge pull request #205 from benjeffery/fix_ci_2

Make CI single threaded

Author: benjeffery

.circleci/config.yml

@@ -9,7 +9,6 @@ jobs:
           name: Install dependencies and set PATH
           command: |
               # Need gsl-dev for msprime. Alternatively we could install via conda
-              # bump
               sudo apt-get update
               sudo apt-get install libgsl-dev
               # way to set path persistently https://circleci.com/docs/2.0/env-vars/#setting-path
@@ -38,5 +37,5 @@ jobs:
       - run:
           name: Run Python tests
           command: |
-              python -m pytest --cov=tsdate  --cov-report=xml --cov-branch tests
+              python -m pytest -vv -n0 --cov=tsdate  --cov-report=xml --cov-branch tests
               python3 -m codecov