ci: create coverage report

.gitlab-ci.yml

@@ -26,6 +26,12 @@ run_test_cases:
     - cp config/sample.engine.ini config/engine.ini
   script:
     - make coverage
+  coverage: '/(?i)total.*? (100(?:\.0+)?\%|[1-9]?\d(?:\.\d+)?\%)$/'
+  artifacts:
+    reports:
+      coverage_report:
+        coverage_format: cobertura
+        path: coverage.xml
 
 check_style:
   stage: test