GraphEdit docs not fully up to date with changes.

**Your Godot version:** 4.2.1

**Issue description:** GraphEdit and related nodes documentation

**URL to the documentation page:**
(1) https://docs.godotengine.org/en/4.1/classes/class_graphnode.html
(2) https://docs.godotengine.org/en/stable/classes/class_graphedit.html
(3) https://docs.godotengine.org/en/stable/tutorials/migrating/upgrading_to_godot_4.2.html

There's been changes going from 4.1 to 4.2 to the GraphEdit and related nodes which have not been fully documented; I've found at least a few issues so far;

1. In (1), `GraphEdit`'s `get_connection_list` has a different output Dictionary from before, the documentation still says the Dictionary is of the form `{ from_port: 0, from: "GraphNode name 0", to_port: 1, to: "GraphNode name 1" }`, but in 4.2 it seems to have been changed to `{ from_port: 0, from_node: "GraphNode name 0", to_port: 1, to_node: "GraphNode name 1" }`.

2. "Method `get_connection_output_count` removed" in (3) should be "Method `get_connection_output_count` replaced by `get_output_port_count`". I assume similar things happens for other methods which the upgrading docs mention have been removed, but instead seem to have been replaced.

There might be more, I'll comment here if I find anything else while migrating.