03-filesystems.sh: too emergency_shell prone? about void-runit

[gt7-void]

More info: I had forgotten that a few months ago I had tested btrfs in this server. I think I erased everything but apparently the disk still "looks like" a btrfs (partitionless) disk:

# file -s /dev/sde
/dev/sde: BTRFS Filesystem ...

In fact, in a system without any disk that "looks like btrfs", running btrfs device scan does not result in a failure, even if btrfs is blacklisted.

Summary: I had to do TWO non-standard things to trigger this (unexpected, undesired) behaviour: blacklist btrfs AND have a disk that was formatted with btrfs at some poin

[Goorzhel]

Would it not be simpler to uninstall btrfs-progs so as to not trip the [ -x /bin/btrfs ] test?

$ xbps-query -o $(which btrfs)
btrfs-progs-5.11.1_1: /usr/bin/btrfs (regular file)