### 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 op_result = codegen.add_temporary(_gdtype_from_datatype(assignment->get_datatype(), codegen.script));
					GDScriptCodeGenerator::Address member = codegen.add_temporary(_gdtype_from_datatype(assignment->assignee->get_datatype(), codegen.script));
					gen->write_get_member(member, name);
					gen->write_binary_operator(op_result, assignment->variant_op, member, assigned_value);
					gen->pop_temporary(); 
					to_assign = op_result;
				}
				gen->write_set_member(to_assign, name);
				if (to_assign.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
					gen->pop_temporary(); 
				}
				if (has_operation && assigned_value.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
					gen->pop_temporary(); 
				}
			} else {
				
				ERR_FAIL_COND_V_MSG(assignment->assignee->type != GDScriptParser::Node::IDENTIFIER, GDScriptCodeGenerator::Address(), "Expected the assignee to be an identifier here.");
				GDScriptCodeGenerator::Address member;
				bool is_member = false;
				bool has_setter = false;
				bool is_in_setter = false;
				bool is_static = false;
				GDScriptCodeGenerator::Address static_var_class;
				int static_var_index = 0;
				GDScriptDataType static_var_data_type;
				StringName var_name;
				StringName setter_function;
				var_name = static_cast<const GDScriptParser::IdentifierNode *>(assignment->assignee)->name;
				if (!_is_local_or_parameter(codegen, var_name)) {
					if (codegen.script->member_indices.has(var_name)) {