CI: Rename generate_summary -> github_summary

Change-Id: Iac698adc097e092f646ce0a650bc781356e5348e
Signed-off-by: Matthew Watkins <mwatkins@linuxfoundation.org>

Author: ModeSevenIndustrialSolutions

.github/workflows/github2gerrit.yaml

@@ -74,7 +74,7 @@ jobs:
         uses: modeseven-lfreleng-actions/repository-metadata-action@gerrit-metadata  # Testing
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          generate_summary: 'false'
+          github_summary: 'false'
           artifact_upload: 'true'
           artifact_formats: 'json'