Prevent configuring a node to a placeholder nodeId (#8342)

Litegraph uses `-1 ` as a placeholder node id to indicate that a node
should be assigned a new node id when added to the graph. Under some
unknown circumstances it's possible for a node to have this placeholder
id saved in a workflow file.

When this occurs, the node is loaded and assigned a new id, but then
configured back to the placeholder id. This PR makes it so the newly
assigned id is kept instead.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8342-Prevent-configuring-a-node-to-a-placehodler-nodeId-2f56d73d365081ed8217e989187b15c8)
by [Unito](https://www.unito.io)

src/lib/litegraph/src/LGraphNode.ts

@@ -785,6 +785,7 @@ export class LGraphNode
     if (this.graph) {
       this.graph._version++
     }
+    if (info.id === -1) info.id = this.id
     for (const j in info) {
       if (j == 'properties') {
         // i don't want to clone properties, I want to reuse the old container