[Streamlit sharing] Importerror: libgl.so.1: cannot open shared object file: no such file or directory opencv error [

Hello guys i am getting the same errors as above but i have deployed the app through heroku, it is successfully deployed but getting an error same as above please help.

this is the content of my requirement.txt file:
streamlit==0.84.1
opencv-python-headless
numpy==1.19.5
Pillow==8.2.0
mediapipe==0.8.6
face-recognition==1.3.0

link to deployed app:
https://facerecog-streamlit.herokuapp.com/