Ignore iso9600 filesystem on Linux (#1355)

The filesystem is read-only and is often used for a virtual FS
with a configuration file for a virtual machine.

Signed-off-by: Leonid Evdokimov <leon@darkk.net.ru>

collector/filesystem_linux.go

@@ -30,7 +30,7 @@ import (
 
 const (
 	defIgnoredMountPoints = "^/(dev|proc|sys|var/lib/docker/.+)($|/)"
-	defIgnoredFSTypes     = "^(autofs|binfmt_misc|bpf|cgroup2?|configfs|debugfs|devpts|devtmpfs|fusectl|hugetlbfs|mqueue|nsfs|overlay|proc|procfs|pstore|rpc_pipefs|securityfs|selinuxfs|squashfs|sysfs|tracefs)$"
+	defIgnoredFSTypes     = "^(autofs|binfmt_misc|bpf|cgroup2?|configfs|debugfs|devpts|devtmpfs|fusectl|hugetlbfs|iso9660|mqueue|nsfs|overlay|proc|procfs|pstore|rpc_pipefs|securityfs|selinuxfs|squashfs|sysfs|tracefs)$"
 	mountTimeout          = 30 * time.Second
 )