docs(integrations): add GitLab documentation

Author: nachtjasmin

docs/src/docs/welcome/integrations.mdx

@@ -85,4 +85,10 @@ source ~/.bashrc
 
 ## CI Integration
 
+### GitHub Actions
+
 See our [GitHub Action](/welcome/install/#github-actions).
+
+### GitLab CI
+
+For GitLab and its CI, we recommend reading [GitLab's official documentation for golangci-lint integration](https://docs.gitlab.com/ci/testing/code_quality/#golangci-lint).