docs: update readme

Author: appleboy

README.md

@@ -80,20 +80,28 @@ SSH Proxy Setting:
 * proxy_cipher - the allowed cipher algorithms. If unspecified then a sensible
 
 ### Setting up SSH Key
-Make sure to follow the below steps while creating SSH Keys and using them. 
-* Login with username specified in Github Secrets.
-* Generate a RSA Key-Pair. 
-   ```bash 
-   ssh-keygen -t rsa -b 4096 -C "[email protected]"
-   ```
-* Add newly generated key into Authorized keys. Read more about authorized keys [here](https://www.ssh.com/ssh/authorized_keys/).
-    ```bash 
-    cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
-    ```
-* Copy Private Key content and paste in Github Secrets. 
-   ```bash 
-   clip < ~/.ssh/id_rsa
-   ```
+
+Make sure to follow the below steps while creating SSH Keys and using them.
+Login with username specified in Github Secrets. Generate a RSA Key-Pair:
+
+ ```bash
+ ssh-keygen -t rsa -b 4096 -C "[email protected]"
+ ```
+
+Add newly generated key into Authorized keys. Read more about authorized keys [here](https://www.ssh.com/ssh/authorized_keys/).
+
+```bash
+cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
+```
+
+Copy Private Key content and paste in Github Secrets.
+
+```bash
+clip < ~/.ssh/id_rsa
+```
+
+See the detail information about [SSH login without password](http://www.linuxproblem.org/art_9.html)
+
 ### Example
 
 Executing remote ssh commands using password.