doc: fix readme raspbian codeblocks

Author: auphofBSF

docs/README.rst

@@ -263,13 +263,15 @@ The summary reason is that the docker installer uses iptables for nat. Unfortuna
 On the target Raspberry Pi issue the following to resolve or incorporate the SLS before in your custom SLS
 
 .. code-block:: bash
+
     sudo update-alternatives --set iptables /usr/sbin/iptables-legacy
     sudo update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy
     sudo shutdown -r 0  # Do a restart, Docker.d should then function
 
 or the following SLS
 
 .. code-block:: yaml
+
     iptables:
       alternatives.set:
         - path:  /usr/sbin/iptables-legacy