docs: fix outdated example of specifying a custom unix socket

docs/src/content/docs/configuration/index.mdx

@@ -20,7 +20,7 @@ Sometimes, there may be a need to specify a custom docker socket. Cup provides t
 For example, if using Podman, you might do
 
 ```bash
-$ cup -s /run/user/1000/podman/podman.sock check
+$ cup -s unix:///run/user/1000/podman/podman.sock check
 ```
 
 This option is also available in the configuration file and it's best to put it there.

docs/src/content/docs/configuration/socket.mdx

@@ -4,7 +4,7 @@ If you need to specify a custom Docker socket (e.g. because you're using Podman)
 
 ```jsonc
 {
-  "socket": "/run/user/1000/podman/podman.sock"
+  "socket": "unix:///run/user/1000/podman/podman.sock"
   // Other options
 }
 ```
@@ -16,4 +16,4 @@ You can also specify a TCP socket if you're using a remote Docker host or a [pro
   "socket": "tcp://localhost:2375"
   // Other options
 }
-```
+```