Update README.md

Freeze SB version due to deprecation

README.md

@@ -47,11 +47,7 @@ The system is trained with dialogue from the MultiWOZ corpus.
 First of all, please install SpeechBrain with the following command:
 
 ```
-git clone https://github.com/speechbrain/speechbrain
-cd speechbrain
-pip install -r recipes/MultiWOZ/response_generation/llama2/extra_requirements.txt
-pip install -r requirements.txt
-pip install -e .
+pip install speechbrain==1.0.2
 ```
 
 **Note**: Please, take a look [here](https://github.com/speechbrain/speechbrain/blob/develop/recipes/MultiWOZ/response_generation/README.md) for info about dependencies and access tokens.
@@ -89,6 +85,7 @@ To train it from scratch follow these steps:
 
 ```bash
 git clone https://github.com/speechbrain/speechbrain/
+git checkout d9fb58f5693311ae2715dae3208e0fafaaf04a81
 ```
 
 2. Install it: