docs: `mount_flags` takes a slice of strings (#13087)
docs: `mount_flags` takes a slice of strings (#13087)

The description of `mount_flags` provides incorrect example
of the accepted value format.

This fixes the issue by changing the example from a string
`ro,noatime` to a slice of strings `["ro", "noatime"]`.
hashicorp/nomad,hashicorp/nomad,hashicorp/nomad,hashicorp/nomad,hashicorp/nomad,hashicorp/nomad