Remove sudo need on client

[u1735067]

Using method described at https://restic.readthedocs.io/en/stable/080_examples.html#full-backup-without-root

[u1735067]

https://github.com/borgbackup/borg/pull/1183

Maybe we could add something to docs or faq about running borg as non-root, with partial root capabilities?

That would be great 😛

https://github.com/borgbackup/borg/issues/2125

You would need to use setcap cap_dac_read_search+ep for this to work, however, this needs to be done on the python3 binary, not borg, or borgmatic wrapper etc.

I'm not sure, but as BBBS is using the self-extracting borg package and not the system-wide borg (which install python & borg module), the cap might be preserved on the child extracted binary (need to RTFM).

Edit, note to self: maybe avoid being referenced in other projects when that's not useful 😕 (possible while keeping the link?)