fix: Add input append_body and generate_release_notes, set both to true

This should:
Allow us to pass the artifact versions.txt and have it appended to the generated release notes
https://github.com/softprops/action-gh-release/blob/4634c16e79c963813287e889244c50009e7f0981/src/github.ts#L244

.github/workflows/release-artifacts-on-tag.yaml

@@ -23,6 +23,8 @@ jobs:
         uses: softprops/action-gh-release@v1
         with:
           body_path: artifact_versions.txt
+          append_body: true
+          generate_release_notes: true
           files: |
             cosmwasm-artifacts_no-token-factory.tar.gz
             artifact_versions.txt