fixing typo

Author: gulcingulletutan

_episodes/08-diagnostics.md

@@ -340,7 +340,7 @@ available functions and their description can be found in
 ## Diagnostic computation
 
 After grouping and selecting data, we can read individual attributes (such as filename)
-of each item. Here, we have grouped the input data  by ``variables``,                            
+of each item. Here, we have grouped the input data  by ``variables``, 
 so we loop over the variables (line 88). Following this is a call to the
 function ``compute_diagnostic`` (line 93). Let's look at the
 definition of this function in line 42, where the actual analysis of the data is done.