Use external ingest for code search diffs (#4712)

* Use external ingest for code search diffs

For https://github.com/microsoft/vscode/issues/292972

Switches us to use external ingest for code search diffs too

* Add extra file change

* Update package.json config

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Co-authored-by: Raymond Zhao <7199958+rzhao271@users.noreply.github.com>