ci: add test and lint jobs to ci

.editorconfig

@@ -10,3 +10,6 @@ insert_final_newline = true
 charset = utf-8
 indent_style = space
 indent_size = 4
+
+[*.{yml,yaml}]
+indent_size = 2

.gitlab-ci.yml

@@ -1,5 +1,20 @@
-test:
-  stage: test
-  script: npm ci --ignore-scripts --force && npm run test
+before_script:
+  - npm ci --ignore-scripts --force
+
+build:
+  stage: build
+  script: npm run build
+  only:
+    - merge_requests
+
+lint:
+  stage: test
+  script: npm run lint
+  only:
+    - merge_requests
+
+test:
+  stage: test
+  script: npm run test
   only:
     - merge_requests