fix some typos in downloading alpaca_dataset (#98)

docs/multi_gpu.md

@@ -75,7 +75,7 @@ Currently 4 datasets are supported that can be found in [Datasets config file](.
 * `alpaca_dataset` : to get this open source data please download the `aplaca.json` to `ft_dataset` folder.
 
 ```bash
-wget -P ft_dataset https://github.com/tatsu-lab/stanford_alpaca/blob/main/alpaca_data.json
+wget -P ft_datasets https://raw.githubusercontent.com/tatsu-lab/stanford_alpaca/main/alpaca_data.json
 ```
 
 * `samsum_dataset`

docs/single_gpu.md

@@ -47,7 +47,7 @@ Currently 4 datasets are supported that can be found in [Datasets config file](.
 * `alpaca_dataset` : to get this open source data please download the `aplaca.json` to `ft_dataset` folder.
 
 ```bash
-wget -P ft_dataset https://github.com/tatsu-lab/stanford_alpaca/blob/main/alpaca_data.json
+wget -P ft_datasets https://raw.githubusercontent.com/tatsu-lab/stanford_alpaca/main/alpaca_data.json
 ```
 
 * `samsum_dataset`