node: repo: avoid using IDs on elements, as that breaks easily on clusters

node: repo: avoid using IDs on elements, as that breaks easily on clusters

Anything where more instances can exist, even if only for a very
short time, must NOT use `id` as that needs to be unique in all
current instances of components/elements of the whole gui.

Here it broke most of the gui when switching between node, as the new
nodes repo gui was instantiated before the old ones was completely
destroyed, so there where (at least) two elements with the same id ->
💥 boom.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>