Update requirements.txt (ShishirPatil#343)

Running gorilla_falcon_cli.py withou einops package returns the
following error:

ImportError: This modeling file requires the following packages that
were not found in your environment: einops. Run `pip install einops`

inference/requirements.txt

@@ -5,3 +5,4 @@ tqdm==4.65.0
 prompt_toolkit==3.0.38
 sentencepiece==0.1.99
 accelerate==0.19.0
+einops==0.7.0