Limit test paralellization

Author: kbattocchi

azure-pipelines.yml

@@ -169,7 +169,7 @@ jobs:
       - script: 'pip install pytest-runner && python setup.py pytest'
         displayName: 'Unit tests'
         env:
-          PYTEST_ADDOPTS: '-m "not (notebook or automl or dml or causal)"'
+          PYTEST_ADDOPTS: '-m "not (notebook or automl or dml or causal)" -n 2'
           COVERAGE_PROCESS_START: 'setup.cfg'
       - task: PublishTestResults@2
         displayName: 'Publish Test Results **/test-results.xml'
@@ -223,7 +223,7 @@ jobs:
       - script: 'pip install pytest-runner && python setup.py pytest'
         displayName: 'Unit tests'
         env:
-          PYTEST_ADDOPTS: '-m "causal"'
+          PYTEST_ADDOPTS: '-m "causal" -n 1'
           COVERAGE_PROCESS_START: 'setup.cfg'
       - task: PublishTestResults@2
         displayName: 'Publish Test Results **/test-results.xml'