doc improvement: make clear that /etc/hostname must match /etc/hosts

Admins of self-hosted instances may encounter trouble if /etc/hostname does not match /etc/hosts, see for example: https://community.jitsi.org/t/default-jitsi-installation-gives-error-bridge-channel-send-no-opened-channel/23740

The “Jitsi Meet quick install” guide tells you what to put in /etc/hosts but does not elaborate about /etc/hostname. Also in the “Install Jitsi Meet” section it states that Jitsi Meet can be installed without a resolvable FQDN, but this is not consistent with what appears in the “Basic Jitsi Meet install”.

I suggest to change this section thus:

Set up the Fully Qualified Doman Name (FQDN) (optional)

If the machine used to host the Jitsi Meet instance has a FQDN hostname already set up in DNS, `/etc/hostname` must contain this FQDN; if this is not case yet, [change the hostname](https://wiki.debian.org/it/HowTo/ChangeHostname).
Then add the the same FQDN in the `/etc/hosts` file , associating it with the loopback address:
127.0.0.1 localhost meet.example.org
Finally test that you can ping the FQDN with: ping "$(hostname)"

[seanm]

I followed the quick-install doc pretty closely but in the end the web page worked but video and audio didn’t. Various searching got me here. I wiped my VM and started over, following the hostname suggestions in this patch, and now things work. There were some other differences too, so I can’t be sure this was my only problem, but using this setup definitely works.

[saghul]

Oops, landed!