### Godot version

v4.0.stable.official [92bee43ad]

### System information

Steam OS Holo, Steam Deck

### Issue description

Using a `[br]` tag at the end of a line in a documentation comment adds an additional space at the beginning of the following line:

![image](https://user-images.githubusercontent.com/857660/236700815-c78a317f-cdf8-4f3c-8489-41f9559ffe6d.png)


### Steps to reproduce

The script below is what I used to generate the image above:

```gdscript
class_name Test
extends Node

## High-level description
##
## First line of detail.[br]
## Second line of detail.
```

Removing the space between `##` and `Second` doesn't change the output.

The only workaround I've found so far is to remove the linebreak after the `[br]` tag, but this makes the documentation comments harder to read in the editor:

```gdscript
class_name Test
extends Node

## High-level description
##
## First line of detail.[br]Second line of detail.
```

### Minimal reproduction project

N/A
bool has_comment = tokenizer.get_comments().has(p_line);
	
	
	if (!p_must_be_doc || !has_comment) {
		return has_comment;
	}
	return tokenizer.get_comments()[p_line].comment.begins_with("##");
}
String GDScriptParser::get_doc_comment(int p_line, bool p_single_line) {
	const HashMap<int, GDScriptTokenizer::CommentData> &comments = tokenizer.get_comments();
	ERR_FAIL_COND_V(!comments.has(p_line), String());
	if (p_single_line) {
		if (comments[p_line].comment.begins_with("##")) {
			return comments[p_line].comment.trim_prefix("##").strip_edges();
		}
		return "";
	}
	String doc;
	int line = p_line;
	bool in_codeblock = false;
	while (comments.has(line - 1)) {
		if (!comments[line - 1].new_line || !comments[line - 1].comment.begins_with("##")) {
			break;
		}
		line--;
	}
	int codeblock_begins = 0;
	while (comments.has(line)) {
		if (!comments[line].new_line || !comments[line].comment.begins_with("##")) {