### Godot version

4.0.2.stable

### System information

Ubuntu 22.10

### Issue description

This happens when converting a godot3 project to a godot4 project.
Godot3 source
```gdscript
extends Node2D

export(int) var integer := 2
export(Resource) var resource: Resource = null
```

Result
```gdscript
extends Node2D

@export var integer: int := 2
@export var resource: Resource: Resource = null
```

Expected result
```gdscript
extends Node2D

@export var integer := 2
@export var resource: Resource = null
```

If someone can point to where in the code this might be fixed maybe I can fix it myself, sounds like a good first issue.


### Steps to reproduce

Open the given project (or any project really) and convert it to a godot 4 project

### Minimal reproduction project

[Conversion Tool Typing Problem.zip](https://github.com/godotengine/godot/files/11185334/Conversion.Tool.Typing.Problem.zip)

int current_element = 0;
		while (RenamesMap3To4::gdscript_function_renames[current_element][0] != nullptr) {
			String name_3_x = RenamesMap3To4::gdscript_function_renames[current_element][0];
			String name_4_0 = RenamesMap3To4::gdscript_function_renames[current_element][1];
			if (!all_functions.has(name_4_0)) {
				ERR_PRINT(vformat("Missing GDScript function in pair (%s - ===> %s <===)", name_3_x, name_4_0));
				valid = false;
			}
			current_element++;
		}
	}
	if (!valid) {
		ERR_PRINT("Found function which is used in the converter, but it cannot be found in Godot 4. Rename this element or remove its entry if it's obsolete.");
	}
	valid = valid && test_single_array(RenamesMap3To4::enum_renames);
	valid = valid && test_single_array(RenamesMap3To4::class_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::gdscript_function_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::csharp_function_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::gdscript_properties_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::csharp_properties_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::shaders_renames, true);
	valid = valid && test_single_array(RenamesMap3To4::gdscript_signals_renames);
	valid = valid && test_single_array(RenamesMap3To4::project_settings_renames);
	valid = valid && test_single_array(RenamesMap3To4::project_godot_renames);
	valid = valid && test_single_array(RenamesMap3To4::input_map_renames);
	valid = valid && test_single_array(RenamesMap3To4::builtin_types_renames);
	valid = valid && test_single_array(RenamesMap3To4::color_renames);
	return valid;
}
bool ProjectConverter3To4::test_single_array(const char *p_array[][2], bool p_ignore_4_0_name) {