Merge branch 'terraform-pipeline-add-diff' into 'master'

gitlab-ci: Add --diff to terraform fmt command

See merge request archlinux/infrastructure!274

.gitlab-ci.yml

@@ -19,4 +19,4 @@ terraform-validate:
     - cd ../tf-stage2
     - terraform init -backend=false
     - terraform validate
-    - terraform fmt --check
+    - terraform fmt --check --diff