tibeten generating（ligature）issue

[Paul-bl]

I noticed that the ligature functionality seems to be not working as expected. Regardless of the font I use, the ligatures do not appear in the generated data.
For example：
should bebut the generator output is , it just simply put character together.

[Paul-bl]

I have fixed it, I need to add font_size,layout_engine="rapm" argument when loading font, to use ramp I need to install it by pip.
in funtion def _generate_horizontal_text() of computer_text_generator.py image_font = ImageFont.truetype(font=font, size=font_size) ->image_font = ImageFont.truetype(font=font, size=font_size,layout_engine="rapm")