The one-line bash -c string had been re-wrapped mid-command, so bash
ran a bare pkill, then a headless nvim that never exited, and never
reached git pull. launchd won't start a job that is still running, so
the config had stopped updating altogether.
Put one command per line, escape &&, and move PATH into
EnvironmentVariables. Rename the plist to match its label, which is
also the name setup_automations.sh bootstraps; before this, a fresh
install downloaded update-nvim-config.plist and then failed to load it.