docs: add gitlabCI integration example

Author: Mickael Dumand

README.md

@@ -15,3 +15,25 @@ yarn add @getluko/android-rollout-node --dev
 ```
 npx android-rollout-node com.package.app production ./api-google-service_account.json
 ```
+
+## Gitlab CI integration
+
+- .gitlab-ci.yml
+
+```
+stages:
+  - android_rollout
+
+android_rollout:
+  rules:
+    - if: $CI_PIPELINE_SOURCE == "schedule" && $SCHEDULE_TYPE == "android_rollout"
+  stage: android_rollout
+  script:
+    - yarn
+    - yarn release:rollout:android:ci
+```
+
+- $SCHEDULE_TYPE should be configure as `android_rollout` in variables
+- Schedule cron to run it everyday of the week at 10am `0 10 * * 1-7`
+
+![Gitlab CI Pipeline](./docs/gitlab_schedule_pipeline.png "Gitlab CI Schedule")