* improvement: use appropriate paths for systemd example
* improvement: add a configurable postgres write conn string
This adds a new configurable connection string for postgres writes.
* improvement: document pg connection_write config
* build: upgrade checkout action for github ci
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Co-authored-by: Petr Kracik <petrkr@petrkr.net>
Co-authored-by: Kieran <kieran@harkin.me>
Co-authored-by: Greg Heartsfield <scsibug@imap.cc>
