In developer VM creation docs, change nsswitch.conf

The line that reads:

hosts: mymachines resolve [!UNAVAIL=return] files myhostname dns

needs to become:

hosts: resolve mymachines [!UNAVAIL=return] files myhostname dns

so that users can use /etc/hosts (by way of the systemd stub resolver) to override the container naming. This is needed to use IPv4 to talk to the container, which is something Mastodon needs.