google-chrome: delete launchctl services only with zap

[i0ntempest]

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[i0ntempest]

Reasons:

1. Currently only launchctl plists are removed when uninstalling, but the actual executables are kept unless one executes zap. Makes no sense to me.
2. Google software update service is used by a lot of other google softwares (e.g. multiple versions of Chrome, Google Drive), deleting this service borks automatic update for all installed google softwares. And for this reason, I suggest we do this for all Google softwares in this repo.