### 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_ADDITION,
			OP_SUBTRACTION,
			OP_MULTIPLICATION,
			OP_DIVISION,
			OP_MODULO,
			OP_POWER,
			OP_BIT_LEFT_SHIFT,
			OP_BIT_RIGHT_SHIFT,
			OP_BIT_AND,
			OP_BIT_OR,
			OP_BIT_XOR,
			OP_LOGIC_AND,
			OP_LOGIC_OR,
			OP_CONTENT_TEST,
			OP_COMP_EQUAL,
			OP_COMP_NOT_EQUAL,
			OP_COMP_LESS,
			OP_COMP_LESS_EQUAL,
			OP_COMP_GREATER,
			OP_COMP_GREATER_EQUAL,
		};
		OpType operation = OpType::OP_ADDITION;
		Variant::Operator variant_op = Variant::OP_MAX;
		ExpressionNode *left_operand = nullptr;
		ExpressionNode *right_operand = nullptr;
		BinaryOpNode() {