docs: fix linting

Signed-off-by: Luca Di Maio <[email protected]>

Author: 89luca89

docs/README.md

@@ -364,8 +364,10 @@ you can trust me and simply run this in your terminal:
 ```sh
 curl -s https://raw.githubusercontent.com/89luca89/distrobox/main/install | sudo sh
 ```
+
 or using wget
-```
+
+```sh
 wget -qO- https://raw.githubusercontent.com/89luca89/distrobox/main/install | sudo sh
 ```
 
@@ -374,8 +376,10 @@ or if you want to select a custom directory to install without sudo:
 ```sh
 curl -s https://raw.githubusercontent.com/89luca89/distrobox/main/install | sh -s -- --prefix ~/.local
 ```
+
 or using wget
-```
+
+```sh
 wget -qO- https://raw.githubusercontent.com/89luca89/distrobox/main/install | sh -s -- --prefix ~/.local
 ```
 
@@ -384,8 +388,10 @@ If you want to install the last development version, directly from the last comm
 ```sh
 curl -s https://raw.githubusercontent.com/89luca89/distrobox/main/install | sudo sh -s -- --next
 ```
+
 or using wget
-```
+
+```sh
 wget -qO- https://raw.githubusercontent.com/89luca89/distrobox/main/install | sudo sh -s -- --next
 ```
 
@@ -394,8 +400,10 @@ or:
 ```sh
 curl -s https://raw.githubusercontent.com/89luca89/distrobox/main/install | sh -s -- --next --prefix ~/.local
 ```
+
 or using wget
-```
+
+```sh
 wget -qO- https://raw.githubusercontent.com/89luca89/distrobox/main/install | sh -s -- --next --prefix ~/.local
 ```