ci: install pip and require models for coverage

.circleci/config.yml

@@ -8,7 +8,7 @@ jobs:
     docker:
       - image: ubuntu:18.04
     steps:
-      - run: apt-get update ; apt-get install -y make git curl
+      - run: apt-get update ; apt-get install -y make git curl python3-pip
       - checkout
       - run: make install
       - run: pip install -r requirements-test.txt

Makefile

@@ -78,7 +78,7 @@ test: test/assets calamari_models
 	$(PYTHON) -m pytest --continue-on-collection-errors test $(PYTEST_ARGS)
 
 # Run unit tests and determine test coverage
-coverage:
+coverage: test/assets calamari_models
 	coverage erase
 	make test PYTHON="coverage run"
 	coverage report