### Godot version

4.0 stable

### System information

Manjaro Linux, kernel 6.1.1-1-MANJARO, AMD Ryzen 5 3600, AMD RX 580

### Issue description

The `wrap_mode` property of the `TextEdit` node doesn't seem to really do anything. Setting it to `LINE_WRAPPING_BOUNDARY` simply means that there won't be an horizontal scrollbar if the text overshoots the boundary, instead of actually forcing the text to the next line so that it stays visible.

### Steps to reproduce

Create a TextEdit node and set its `wrap_mode` property to `LINE_WRAPPING_BOUNDARY`

### Minimal reproduction project

[WrapBugDemo.zip](https://github.com/godotengine/godot/files/10875969/WrapBugDemo.zip)

for (int i = 0; i < carets.size(); i++) {
		if (p_select) {
			_pre_shift_selection(i);
		} else {
			deselect(i);
		}
		Point2i next_line = get_next_visible_line_index_offset_from(get_caret_line(i), get_caret_wrap_index(i), -get_visible_line_count());
		int n_line = get_caret_line(i) - next_line.x + 1;
		set_caret_line(n_line, i == 0, false, next_line.y, i);
		if (p_select) {
			_post_shift_selection(i);
		}
	}
	merge_overlapping_carets();
}
void TextEdit::_move_caret_page_down(bool p_select) {