### 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
GDScriptCodeGenerator::Address assigned = _parse_expression(codegen, r_error, assignment->assigned_value);
				if (r_error) {
					return GDScriptCodeGenerator::Address();
				}
				
				GDScriptCodeGenerator::Address key;
				StringName name;
				if (subscript->is_attribute) {
					name = subscript->attribute->name;
				} else {
					key = _parse_expression(codegen, r_error, subscript->index);
					if (r_error) {
						return GDScriptCodeGenerator::Address();
					}
				}
				
				if (assignment->operation != GDScriptParser::AssignmentNode::OP_NONE) {
					GDScriptCodeGenerator::Address op_result = codegen.add_temporary(_gdtype_from_datatype(assignment->get_datatype(), codegen.script));
					GDScriptCodeGenerator::Address value = codegen.add_temporary(_gdtype_from_datatype(subscript->get_datatype(), codegen.script));
					if (subscript->is_attribute) {
						gen->write_get_named(value, name, prev_base);
					} else {
						gen->write_get(value, key, prev_base);
					}
					gen->write_binary_operator(op_result, assignment->variant_op, value, assigned);
					gen->pop_temporary();
					if (assigned.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
						gen->pop_temporary();
					}