### 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)

Vector<String> found_renames;
	int current_line = 1;
	for (String &line : lines) {
		if (uint64_t(line.length()) <= maximum_line_length) {
			for (unsigned int current_index = 0; RenamesMap3To4::class_renames[current_index][0]; current_index++) {
				if (line.contains(RenamesMap3To4::class_renames[current_index][0])) {
					String old_line = line;
					bool found_ignored_items = false;
					// 
					if (line.contains(String(RenamesMap3To4::class_renames[current_index][0]) + ".")) {
						found_ignored_items = true;
						line = reg_container.class_tscn_regexes[current_index]->sub(line, "TEMP_RENAMED_CLASS.tscn", true);
						line = reg_container.class_gd_regexes[current_index]->sub(line, "TEMP_RENAMED_CLASS.gd", true);
						line = reg_container.class_shader_regexes[current_index]->sub(line, "TEMP_RENAMED_CLASS.shader", true);
					}