### Godot version

4.1

### System information

Windows

### Issue description

Being able to have multiple cursors similarly to vscode is a great feature, however it's only possible to add carets, not remove them. By left clicking you can remove all extra cursors but you cannot remove a specific one so after selecting multiple lines a single missclick, you have to reselect them all again. Looking at the original pr there was a remove_caret function added so it would make sense to be able to remove carets when clicking again, like in vscode.

![image](https://github.com/godotengine/godot/assets/19669673/3867c00e-9faa-4429-9c6d-f2d6d3883044)


### Steps to reproduce

- Alt click to add multiple carets
- Alt click on the same position again
- Nothing happens

### Minimal reproduction project

N/A
ERR_FAIL_INDEX(p_from_line, text.size());
	ERR_FAIL_INDEX(p_from_column, text[p_from_line].length() + 1);
	ERR_FAIL_INDEX(p_to_line, text.size());
	ERR_FAIL_INDEX(p_to_column, text[p_to_line].length() + 1);
	ERR_FAIL_COND(p_to_line < p_from_line); 
	ERR_FAIL_COND(p_to_line == p_from_line && p_to_column < p_from_column); 
	String pre_text = text[p_from_line].substr(0, p_from_column);
	String post_text = text[p_to_line].substr(p_to_column, text[p_to_line].length());
	text.remove_range(p_from_line, p_to_line);
	text.set(p_from_line, pre_text + post_text, structured_text_parser(st_parser, st_args, pre_text + post_text));
	if (!text_changed_dirty && !setting_text) {
		if (is_inside_tree()) {
			MessageQueue::get_singleton()->push_call(this, "_text_changed_emit");
		}
		text_changed_dirty = true;
	}
	emit_signal(SNAME("lines_edited_from"), p_to_line, p_from_line);
}
TextEdit::TextEdit(const String &p_placeholder) {
	placeholder_data_buf.instantiate();
	carets.push_back(Caret());
	clear();
	set_focus_mode(FOCUS_ALL);
	set_default_cursor_shape(CURSOR_IBEAM);