Update 21-1st-workflow.md

Author: mr-c

_episodes/21-1st-workflow.md

@@ -137,4 +137,4 @@ connecting the input parameter `src` to the output parameter of `untar` using
 `untar/example_out`.  The output of this step `classfile` is connected to the
 `outputs` section for the Workflow, described above.
 
-[params]: 06-params/
+[params]: ../06-params/