Updated SC2009 (markdown)

SC2009.md

@@ -34,7 +34,7 @@ This is more robust than `ps .. | grep python | cut ..` because it does not try
 
 You can [[ignore]] this error if you are trying to match against something that `pgrep` doesn't support:
 
-```
+```sh
 # pgrep does not support filtering by 'nice' value
 # shellcheck disable=SC2009
 ps -axo nice=,pid= | grep -v '^  0'