Old versions of fuse have read-only config file

[afbjorklund]

Description

This causes the probe to loop on startup, even though everything is fine.

INFO[0011] [hostagent] Waiting for the essential requirement 4 of 4: "/etc/fuse.conf (/etc/fuse3.conf) to contain \"user_allow_other\"" 
INFO[0051] [hostagent] Waiting for the essential requirement 4 of 4: "/etc/fuse.conf (/etc/fuse3.conf) to contain \"user_allow_other\"" 
INFO[0091] [hostagent] Waiting for the essential requirement 4 of 4: "/etc/fuse.conf (/etc/fuse3.conf) to contain \"user_allow_other\"" 

-rw-r----- 1 root fuse 297 Jun 3 15:31 /etc/fuse.conf

Seen with Ubuntu 15.04, but only when enabling the mounts (with sshfs)

---

The default was changed in Ubuntu 20.04 (fuse 2.9.3-5)

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=733312

The workaround was to disable the mounts (for k8s v1.0.0)

mounts: []

[afbjorklund]

i.e. suggested change is to use 'sudo grep`, when checking for the config

pkg/cidata/cidata.TEMPLATE.d/boot/35-setup-packages.sh: if ! grep -q "^user_allow_other" "${fuse_conf}"; then