### 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)

if (from.size() > 200) {
		from = from.substr(0, 197) + "...";
	}
	if (to.size() > 200) {
		to = to.substr(0, 197) + "...";
	}
	if (line.size() > 400) {
		line = line.substr(0, 397) + "...";
	}
	from = from.strip_escapes();
	to = to.strip_escapes();
	line = line.replace("\r", "").replace("\n", "").strip_edges();
	return vformat("Line(%d), %s -> %s  -  LINE \"\"\" %s \"\"\"", current_line, from, to, line);
}
// Prints only full lines e.g.:
// Line (1) - FULL LINES - """yield(get_tree().create_timer(3), 'timeout')"""  =====>  """ await get_tree().create_timer(3).timeout """
String ProjectConverter3To4::simple_line_formatter(int current_line, String old_line, String new_line) {