### Godot version

4.0.2.stable.mono

### System information

Windows 10 - 4.0.2.stable.mono - Any Renderer

### Issue description

In a script with an `@export` variable (with a non-default value), Godot will replace the first variable in the category with the same name. For example, if you're exporting a variable called "Vector", and the value is set to a non-default value, the first variable in the category called "Vector" will also be changed to the same value.

### Steps to reproduce

Attach said script to a node:
```
extends Node

@export var Vector: Vector2
@export_category("Vector")
@export var Var2: float = 1

func _process(delta):
	print(Var2)
```
When changing the value of the `Vector` export variable, the variable Var2 will contain the same value. This does not happen when the `@export_category` has a different name.

### Minimal reproduction project

N/A
type = GET_NODE;
		}
	};
	struct IdentifierNode : public ExpressionNode {
		StringName name;
		enum Source {
			UNDEFINED_SOURCE,
			FUNCTION_PARAMETER,
			LOCAL_CONSTANT,
			LOCAL_VARIABLE,
			LOCAL_ITERATOR, 
			LOCAL_BIND, 
			MEMBER_SIGNAL,
			MEMBER_VARIABLE,
			STATIC_VARIABLE,
			MEMBER_CONSTANT,
			INHERITED_VARIABLE,
		};
		Source source = UNDEFINED_SOURCE;
		union {
			ParameterNode *parameter_source = nullptr;
			ConstantNode *constant_source;
			VariableNode *variable_source;
			IdentifierNode *bind_source;
		};
		FunctionNode *source_function = nullptr;
		int usages = 0; 
		IdentifierNode() {