### 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_COND_V(p_caret > carets.size(), "");
	StringBuilder selected_text;
	Vector<int> caret_edit_order = get_caret_index_edit_order();
	for (int i = caret_edit_order.size() - 1; i >= 0; i--) {
		int caret_idx = caret_edit_order[i];
		if (p_caret != -1 && p_caret != caret_idx) {
			continue;
		}
		if (!has_selection(caret_idx)) {
			continue;
		}
		selected_text += _base_get_text(get_selection_from_line(caret_idx), get_selection_from_column(caret_idx), get_selection_to_line(caret_idx), get_selection_to_column(caret_idx));
		if (p_caret == -1 && i != 0) {
			selected_text += "\n";
		}
	}
	return selected_text.as_string();
}
int TextEdit::get_selection_line(int p_caret) const {