Bump gradio version

Make sure to upgrade with

`pip install -r requirements.txt --upgrade`

requirements.txt

@@ -1,7 +1,7 @@
 accelerate==0.17.1
 bitsandbytes==0.37.1
 flexgen==0.1.7
-gradio==3.18.0
+gradio==3.23.0
 markdown
 numpy
 peft==0.2.0