ansible-inventories/bitegra#21 Rename master to main

.gitlab-ci.yml

@@ -10,4 +10,4 @@ node:
     - docker build --pull --build-arg NODE_VERSION=${VERSION} -t $CI_REGISTRY_IMAGE:${VERSION} .
     - docker push $CI_REGISTRY_IMAGE:${VERSION}
   only:
-    - master
+    - main