set pytorch-lightning version to 1.6.5 (newer version throws an error)

app.py

@@ -1,7 +1,7 @@
 import os
 
 os.system("git clone --recursive https://github.com/JD-P/cloob-latent-diffusion")
-os.system("cd cloob-latent-diffusion;pip install omegaconf pillow pytorch-lightning einops wandb ftfy regex ./CLIP")
+os.system("cd cloob-latent-diffusion;pip install omegaconf pillow pytorch-lightning==1.6.5 einops wandb ftfy regex ./CLIP")
 
 import argparse
 from functools import partial