Godot: GDScript: duplicate keys in dictionary is parsed without error

[ThakeeNathees]

Godot version: v4.0.dev.custom_build 35ff38b3d

OS/device including version: windows 10

Issue description:

func _ready():
    var d = {
        "duplicate_key": 1,
        "duplicate_key": 2, ## <-- this should be invalid
    }
    print(d)

[Calinou]

In comparison, 3.2.2 will mark an error about "Duplicate key found in Dictionary literal".

By the way, it would be nice if the key name in question was mentioned in the error message.

[vnen]

This was fixed by #41381

[vnen]

FYI current message is now this: Parse Error: Key "duplicate_key" was already used in this dictionary (at line 5).