How to mount ceph temporarily

[sfmig]

A guide on how to mount a ceph partition temporarily (i.e., it will be unmounted in the next reboot)

Feel free to edit to match to overall style - I followed the other ceph mounting guide mostly, just added a steps section.

Thanks @niksirbi !

[niksirbi]

Hey @sfmig, thanks a lot! This looks good.
The reason CI was failing is that we have recently added an automatic URL link-checker to our docs-building action, so it was flagging broken links, which I proceeded to either fix or ignore in conf.py (if they were "false positives").

I did some minor rewording and restructured the permanent guide so that it mirrors the temporary guide's structure (I liked your idea of "Steps").

I also cross-referenced the permanent/temporary guide using explicit reference targets, so the links won't break even if we move the files around in the future.

I will merge this now.