Use code quotes for cmds in docs

spn/testing/simple/README.md

@@ -33,7 +33,9 @@ For testing just one Hub with a different build or config, you can simply use `.
 
 For connecting to the SPN test network with Portmaster, execute portmaster like this:
 
+```
 sudo ../../../cmds/portmaster-core/portmaster-core --disable-shutdown-event --devmode --log debug --data /opt/safing/portmaster --spn-map test --bootstrap-file ./testdata/shared/bootstrap.dsd
+```
 
 Note:
 This uses the same portmaster data and config as your installed version.