Adding signoff option for version workflow PR (opensearch-project#143)

Signed-off-by: Vacha Shah <vachshah@amazon.com>

Author: VachaShah

.github/workflows/version.yml

@@ -46,6 +46,7 @@ jobs:
           token: ${{ steps.github_app_token.outputs.token }}
           base: ${{ env.BASE }}
           commit-message: Incremented version to ${{ env.NEXT_VERSION }}
+          signoff: true
           delete-branch: true
           title: '[AUTO] Incremented version to ${{ env.NEXT_VERSION }}.'
           body: |