Add proper release notes

.gitlab-ci.yml

@@ -114,10 +114,16 @@ create-release:
   image: registry.gitlab.com/gitlab-org/release-cli:latest
   rules:
     - if: $CI_COMMIT_TAG =~ /\d+/
-  script: echo "Creating release $CI_COMMIT_TAG"
+  before_script:
+    - apk add --update yq envsubst
+  script: 
+    - echo "Creating release $CI_COMMIT_TAG"
+    - AVAILABLE_OPENTOFU_VERSIONS=$(yq -r '.spec.inputs.opentofu_version.options | .[] | "- [`" + . + "`](https://github.com/opentofu/opentofu/releases/tag/v" + . + ")"' templates/full-pipeline.yml)
+    - export AVAILABLE_OPENTOFU_VERSIONS
+    - cat .gitlab/release-template.md | envsubst > release-notes.md 
   release:
     tag_name: $CI_COMMIT_TAG
-    description: "Release $CI_COMMIT_TAG of components repository $CI_PROJECT_PATH"
+    description: './release-notes.md'
 
 old-states:
   image: alpine:latest

.gitlab/release-template.md

+Release $CI_COMMIT_TAG of components repository $CI_PROJECT_PATH.
+
+## Usage
+
+You can use the OpenTofu CI/CD component from the CI/CD catalog using:
+
+```yaml
+include:
+  - component: gitlab.com/components/opentofu/full-pipeline@$CI_COMMIT_TAG
+    inputs:
+      # The version must currently be specified explicitly as an input,
+      # to find the correctly associated images. # This can be removed 
+      # once https://gitlab.com/gitlab-org/gitlab/-/issues/438275 is solved.
+      version: $CI_COMMIT_TAG
+      opentofu_version: $LATEST_OPENTOFU_VERSION
+
+stages: [validate, test, build, deploy, cleanup]
+```
+
+See the [README.md](README.md) for more usage examples.
+
+## Available OpenTofu versions
+
+This release is available with the following OpenTofu versions:
+
+$AVAILABLE_OPENTOFU_VERSIONS