feat(ci): release docs as alpha when doing a pre-release (#1624)

Co-authored-by: Heitor Lessa <lessa@amazon.nl>

Author: rubenfonseca

.github/workflows/on_release_notes.yml

@@ -44,6 +44,11 @@ on:
         default: false
         type: boolean
         required: false
+      pre_release:
+        description: "Publishes documentation using a pre-release tag. You are still responsible for passing a pre-release version tag to the workflow."
+        default: false
+        type: boolean
+        required: false
 
 jobs:
   release:
@@ -113,15 +118,30 @@ jobs:
       contents: write
     uses: ./.github/workflows/reusable_publish_changelog.yml
 
+  # When doing a pre-release, we want to publish the docs as "alpha" instead of replacing the latest docs
+  prepare_docs_alias:
+    runs-on: ubuntu-latest
+    outputs:
+      DOCS_ALIAS: ${{ steps.set-alias.outputs.DOCS_ALIAS }}
+    steps:
+      - name: Set docs alias
+        id: set-alias
+        run: |
+          DOCS_ALIAS=latest
+          if [[ "${{ github.event.release.prerelease || inputs.pre_release }}" == true ]] ; then
+            DOCS_ALIAS=alpha
+          fi
+          echo DOCS_ALIAS="$DOCS_ALIAS" >> "$GITHUB_OUTPUT"
+
   docs:
-    needs: [release, changelog]
+    needs: [release, changelog, prepare_docs_alias]
     permissions:
       contents: write
       pages: write
     uses: ./.github/workflows/reusable_publish_docs.yml
     with:
       version: ${{ needs.release.outputs.RELEASE_VERSION }}
-      alias: latest
+      alias: ${{ needs.prepare_docs_alias.outputs.DOCS_ALIAS }}
       detached_mode: true
 
   publish_layer: