### 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 end = line.size() - 1; // 
	int variable_start = end - 1;
	int start = end - 1;
	bool is_possibly_nodepath = false;
	bool is_valid_nodepath = false;
	while (start >= 0) {
		char32_t character = line[start];
		bool is_variable_char = (character >= 'A' && character <= 'Z') || (character >= 'a' && character <= 'z') || character == '.' || character == '_';
		bool is_nodepath_start = character == '$';
		bool is_nodepath_sep = character == '/';
		if (is_variable_char || is_nodepath_start || is_nodepath_sep) {
			if (start == 0) {
				break;
			} else if (is_nodepath_sep) {
				// 
				is_possibly_nodepath = true;
			} else if (is_nodepath_start) {
				// 
				is_valid_nodepath = true;
				break;
			}
			if (!is_possibly_nodepath) {
				variable_start--;