### 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
OP_NONE,
			OP_ADDITION,
			OP_SUBTRACTION,
			OP_MULTIPLICATION,
			OP_DIVISION,
			OP_MODULO,
			OP_POWER,
			OP_BIT_SHIFT_LEFT,
			OP_BIT_SHIFT_RIGHT,
			OP_BIT_AND,
			OP_BIT_OR,
			OP_BIT_XOR,
		};
		Operation operation = OP_NONE;
		Variant::Operator variant_op = Variant::OP_MAX;
		ExpressionNode *assignee = nullptr;
		ExpressionNode *assigned_value = nullptr;
		bool use_conversion_assign = false;
		AssignmentNode() {
			type = ASSIGNMENT;
		}
	};
	struct AwaitNode : public ExpressionNode {
		ExpressionNode *to_await = nullptr;
		AwaitNode() {
			type = AWAIT;
		}
	};
	struct BinaryOpNode : public ExpressionNode {
		enum OpType {