CI: build and test in same phase

.gitlab-ci.yml

@@ -7,14 +7,10 @@ before_script:
   - pwd
   - pip3 install networkx
 
-build:
-  stage: build
-  script:
-    - pip3 install .
-
 test:
   stage: test
   coverage: '/(?i)total.*? (100(?:\.0+)?\%|[1-9]?\d(?:\.\d+)?\%)$/'
   script:
+    - pip3 install .
     - pytest --cov=.